<!doctype html><html lang="en">
 <head>
  <meta content="text/html; charset=utf-8" http-equiv="Content-Type">
  <title>Import Maps</title>
  <meta content="width=device-width, initial-scale=1, shrink-to-fit=no" name="viewport">
<style data-fill-with="stylesheet">/******************************************************************************
 *                   Style sheet for the W3C specifications                   *
 *
 * Special classes handled by this style sheet include:
 *
 * Indices
 *   - .toc for the Table of Contents (<ol class="toc">)
 *     + <span class="secno"> for the section numbers
 *   - #toc for the Table of Contents (<nav id="toc">)
 *   - ul.index for Indices (<a href="#ref">term</a><span>, in §N.M</span>)
 *   - table.index for Index Tables (e.g. for properties or elements)
 *
 * Structural Markup
 *   - table.data for general data tables
 *     -> use 'scope' attribute, <colgroup>, <thead>, and <tbody> for best results !
 *     -> use <table class='complex data'> for extra-complex tables
 *     -> use <td class='long'> for paragraph-length cell content
 *     -> use <td class='pre'> when manual line breaks/indentation would help readability
 *   - dl.switch for switch statements
 *   - ol.algorithm for algorithms (helps to visualize nesting)
 *   - .figure and .caption (HTML4) and figure and figcaption (HTML5)
 *     -> .sidefigure for right-floated figures
 *   - ins/del
 *
 * Code
 *   - pre and code
 *
 * Special Sections
 *   - .note       for informative notes             (div, p, span, aside, details)
 *   - .example    for informative examples          (div, p, pre, span)
 *   - .issue      for issues                        (div, p, span)
 *   - .assertion  for assertions                    (div, p, span)
 *   - .advisement for loud normative statements     (div, p, strong)
 *   - .annoying-warning for spec obsoletion notices (div, aside, details)
 *
 * Definition Boxes
 *   - pre.def   for WebIDL definitions
 *   - table.def for tables that define other entities (e.g. CSS properties)
 *   - dl.def    for definition lists that define other entitles (e.g. HTML elements)
 *
 * Numbering
 *   - .secno for section numbers in .toc and headings (<span class='secno'>3.2</span>)
 *   - .marker for source-inserted example/figure/issue numbers (<span class='marker'>Issue 4</span>)
 *   - ::before styled for CSS-generated issue/example/figure numbers:
 *     -> Documents wishing to use this only need to add
 *        figcaption::before,
 *        .caption::before { content: "Figure "  counter(figure) " ";  }
 *        .example::before { content: "Example " counter(example) " "; }
 *        .issue::before   { content: "Issue "   counter(issue) " ";   }
 *
 * Header Stuff (ignore, just don't conflict with these classes)
 *   - .head for the header
 *   - .copyright for the copyright
 *
 * Miscellaneous
 *   - .overlarge for things that should be as wide as possible, even if
 *     that overflows the body text area. This can be used on an item or
 *     on its container, depending on the effect desired.
 *     Note that this styling basically doesn't help at all when printing,
 *     since A4 paper isn't much wider than the max-width here.
 *     It's better to design things to fit into a narrower measure if possible.
 *   - js-added ToC jump links (see fixup.js)
 *
 ******************************************************************************/

/******************************************************************************/
/*                                   Body                                     */
/******************************************************************************/

	body {
		counter-reset: example figure issue;

		/* Layout */
		max-width: 50em;               /* limit line length to 50em for readability   */
		margin: 0 auto;                /* center text within page                     */
		padding: 1.6em 1.5em 2em 50px; /* assume 16px font size for downlevel clients */
		padding: 1.6em 1.5em 2em calc(26px + 1.5em); /* leave space for status flag     */

		/* Typography */
		line-height: 1.5;
		font-family: sans-serif;
		widows: 2;
		orphans: 2;
		word-wrap: break-word;
		overflow-wrap: break-word;
		hyphens: auto;

		/* Colors */
		color: black;
		background: white top left fixed no-repeat;
		background-size: 25px auto;
	}


/******************************************************************************/
/*                         Front Matter & Navigation                          */
/******************************************************************************/

/** Header ********************************************************************/

	div.head { margin-bottom: 1em }
	div.head hr { border-style: solid; }

	div.head h1 {
		font-weight: bold;
		margin: 0 0 .1em;
		font-size: 220%;
	}

	div.head h2 { margin-bottom: 1.5em;}

/** W3C Logo ******************************************************************/

	.head .logo {
		float: right;
		margin: 0.4rem 0 0.2rem .4rem;
	}

	.head img[src*="logos/W3C"] {
		display: block;
		border: solid #1a5e9a;
		border-width: .65rem .7rem .6rem;
		border-radius: .4rem;
		background: #1a5e9a;
		color: white;
		font-weight: bold;
	}

	.head a:hover > img[src*="logos/W3C"],
	.head a:focus > img[src*="logos/W3C"] {
		opacity: .8;
	}

	.head a:active > img[src*="logos/W3C"] {
		background: #c00;
		border-color: #c00;
	}

	/* see also additional rules in Link Styling section */

/** Copyright *****************************************************************/

	p.copyright,
	p.copyright small { font-size: small }

/** Back to Top / ToC Toggle **************************************************/

	@media print {
		#toc-nav {
			display: none;
		}
	}
	@media not print {
		#toc-nav {
			position: fixed;
			z-index: 2;
			bottom: 0; left: 0;
			margin: 0;
			min-width: 1.33em;
			border-top-right-radius: 2rem;
			box-shadow: 0 0 2px;
			font-size: 1.5em;
			color: black;
		}
		#toc-nav > a {
			display: block;
			white-space: nowrap;

			height: 1.33em;
			padding: .1em 0.3em;
			margin: 0;

			background: white;
			box-shadow: 0 0 2px;
			border: none;
			border-top-right-radius: 1.33em;
			background: white;
		}
		#toc-nav > #toc-jump {
			padding-bottom: 2em;
			margin-bottom: -1.9em;
		}

		#toc-nav > a:hover,
		#toc-nav > a:focus {
			background: #f8f8f8;
		}
		#toc-nav > a:not(:hover):not(:focus) {
			color: #707070;
		}

		/* statusbar gets in the way on keyboard focus; remove once browsers fix */
		#toc-nav > a[href="#toc"]:not(:hover):focus:last-child {
			padding-bottom: 1.5rem;
		}

		#toc-nav:not(:hover) > a:not(:focus) > span + span {
			/* Ideally this uses :focus-within on #toc-nav */
			display: none;
		}
		#toc-nav > a > span + span {
			padding-right: 0.2em;
		}

		#toc-toggle-inline {
			vertical-align: 0.05em;
			font-size: 80%;
			color: gray;
			color: hsla(203,20%,40%,.7);
			border-style: none;
			background: transparent;
			position: relative;
		}
		#toc-toggle-inline:hover:not(:active),
		#toc-toggle-inline:focus:not(:active) {
			text-shadow: 1px 1px silver;
			top: -1px;
			left: -1px;
		}

		#toc-nav :active {
			color: #C00;
		}
	}

/** ToC Sidebar ***************************************************************/

	/* Floating sidebar */
	@media screen {
		body.toc-sidebar #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			max-width: 80%;
			max-width: calc(100% - 2em - 26px);
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			background: inherit;
			background-color: #f7f8f9;
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
		}
		body.toc-sidebar #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
		}
		body.toc-sidebar #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	/* Hide main scroller when only the ToC is visible anyway */
	@media screen and (max-width: 28em) {
		body.toc-sidebar {
			overflow: hidden;
		}
	}

	/* Sidebar with its own space */
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) #toc {
			position: fixed;
			top: 0; bottom: 0;
			left: 0;
			width: 23.5em;
			overflow: auto;
			padding: 0 1em;
			padding-left: 42px;
			padding-left: calc(1em + 26px);
			background: inherit;
			background-color: #f7f8f9;
			z-index: 1;
			box-shadow: -.1em 0 .25em rgba(0,0,0,.1) inset;
		}
		body:not(.toc-inline) #toc h2 {
			margin-top: .8rem;
			font-variant: small-caps;
			font-variant: all-small-caps;
			text-transform: lowercase;
			font-weight: bold;
			color: gray;
			color: hsla(203,20%,40%,.7);
		}

		body:not(.toc-inline) {
			padding-left: 29em;
		}
		/* See also Overflow section at the bottom */

		body:not(.toc-inline) #toc-jump:not(:focus) {
			width: 0;
			height: 0;
			padding: 0;
			position: absolute;
			overflow: hidden;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) {
			margin: 0 4em;
		}
	}

/******************************************************************************/
/*                                Sectioning                                  */
/******************************************************************************/

/** Headings ******************************************************************/

	h1, h2, h3, h4, h5, h6, dt {
		page-break-after: avoid;
		page-break-inside: avoid;
		font: 100% sans-serif;   /* Reset all font styling to clear out UA styles */
		font-family: inherit;    /* Inherit the font family. */
		line-height: 1.2;        /* Keep wrapped headings compact */
		hyphens: manual;         /* Hyphenated headings look weird */
	}

	h2, h3, h4, h5, h6 {
		margin-top: 3rem;
	}

	h1, h2, h3 {
		color: #005A9C;
		background: transparent;
	}

	h1 { font-size: 170%; }
	h2 { font-size: 140%; }
	h3 { font-size: 120%; }
	h4 { font-weight: bold; }
	h5 { font-style: italic; }
	h6 { font-variant: small-caps; }
	dt { font-weight: bold; }

/** Subheadings ***************************************************************/

	h1 + h2,
	#subtitle {
		/* #subtitle is a subtitle in an H2 under the H1 */
		margin-top: 0;
	}
	h2 + h3,
	h3 + h4,
	h4 + h5,
	h5 + h6 {
		margin-top: 1.2em; /* = 1 x line-height */
	}

/** Section divider ***********************************************************/

	:not(.head) > hr {
		font-size: 1.5em;
		text-align: center;
		margin: 1em auto;
		height: auto;
		border: transparent solid 0;
		background: transparent;
	}
	:not(.head) > hr::before {
		content: "\2727\2003\2003\2727\2003\2003\2727";
	}

/******************************************************************************/
/*                            Paragraphs and Lists                            */
/******************************************************************************/

	p {
		margin: 1em 0;
	}

	dd > p:first-child,
	li > p:first-child {
		margin-top: 0;
	}

	ul, ol {
		margin-left: 0;
		padding-left: 2em;
	}

	li {
		margin: 0.25em 0 0.5em;
		padding: 0;
	}

	dl dd {
		margin: 0 0 .5em 2em;
	}

	.head dd + dd { /* compact for header */
		margin-top: -.5em;
	}

	/* Style for algorithms */
	ol.algorithm ol:not(.algorithm),
	.algorithm > ol ol:not(.algorithm) {
	 border-left: 0.5em solid #DEF;
	}

	/* Put nice boxes around each algorithm. */
	[data-algorithm]:not(.heading) {
	  padding: .5em;
	  border: thin solid #ddd; border-radius: .5em;
	  margin: .5em calc(-0.5em - 1px);
	}
	[data-algorithm]:not(.heading) > :first-child {
	  margin-top: 0;
	}
	[data-algorithm]:not(.heading) > :last-child {
	  margin-bottom: 0;
	}

	/* Style for switch/case <dl>s */
	dl.switch > dd > ol.only,
	dl.switch > dd > .only > ol {
	 margin-left: 0;
	}
	dl.switch > dd > ol.algorithm,
	dl.switch > dd > .algorithm > ol {
	 margin-left: -2em;
	}
	dl.switch {
	 padding-left: 2em;
	}
	dl.switch > dt {
	 text-indent: -1.5em;
	 margin-top: 1em;
	}
	dl.switch > dt + dt {
	 margin-top: 0;
	}
	dl.switch > dt::before {
	 content: '\21AA';
	 padding: 0 0.5em 0 0;
	 display: inline-block;
	 width: 1em;
	 text-align: right;
	 line-height: 0.5em;
	}

/** Terminology Markup ********************************************************/


/******************************************************************************/
/*                                 Inline Markup                              */
/******************************************************************************/

/** Terminology Markup ********************************************************/
	dfn   { /* Defining instance */
		font-weight: bolder;
	}
	a > i { /* Instance of term */
		font-style: normal;
	}
	dt dfn code, code.idl {
		font-size: medium;
	}
	dfn var {
		font-style: normal;
	}

/** Change Marking ************************************************************/

	del { color: red;  text-decoration: line-through; }
	ins { color: #080; text-decoration: underline;    }

/** Miscellaneous improvements to inline formatting ***************************/

	sup {
		vertical-align: super;
		font-size: 80%
	}

/******************************************************************************/
/*                                    Code                                    */
/******************************************************************************/

/** General monospace/pre rules ***********************************************/

	pre, code, samp {
		font-family: Menlo, Consolas, "DejaVu Sans Mono", Monaco, monospace;
		font-size: .9em;
		page-break-inside: avoid;
		hyphens: none;
		text-transform: none;
	}
	pre code,
	code code {
		font-size: 100%;
	}

	pre {
		margin-top: 1em;
		margin-bottom: 1em;
		overflow: auto;
	}

/** Inline Code fragments *****************************************************/

  /* Do something nice. */

/******************************************************************************/
/*                                    Links                                   */
/******************************************************************************/

/** General Hyperlinks ********************************************************/

	/* We hyperlink a lot, so make it less intrusive */
	a[href] {
		color: #034575;
		text-decoration: none;
		border-bottom: 1px solid #707070;
		/* Need a bit of extending for it to look okay */
		padding: 0 1px 0;
		margin: 0 -1px 0;
	}
	a:visited {
		border-bottom-color: #BBB;
	}

	/* Use distinguishing colors when user is interacting with the link */
	a[href]:focus,
	a[href]:hover {
		background: #f8f8f8;
		background: rgba(75%, 75%, 75%, .25);
		border-bottom-width: 3px;
		margin-bottom: -2px;
	}
	a[href]:active {
		color: #C00;
		border-color: #C00;
	}

	/* Backout above styling for W3C logo */
	.head .logo,
	.head .logo a {
		border: none;
		text-decoration: none;
		background: transparent;
	}

/******************************************************************************/
/*                                    Images                                  */
/******************************************************************************/

	img {
		border-style: none;
	}

	/* For autogen numbers, add
	   .caption::before, figcaption::before { content: "Figure " counter(figure) ". "; }
	*/

	figure, .figure, .sidefigure {
		page-break-inside: avoid;
		text-align: center;
		margin: 2.5em 0;
	}
	.figure img,    .sidefigure img,    figure img,
	.figure object, .sidefigure object, figure object {
		max-width: 100%;
		margin: auto;
	}
	.figure pre, .sidefigure pre, figure pre {
		text-align: left;
		display: table;
		margin: 1em auto;
	}
	.figure table, figure table {
		margin: auto;
	}
	@media screen and (min-width: 20em) {
		.sidefigure {
			float: right;
			width: 50%;
			margin: 0 0 0.5em 0.5em
		}
	}
	.caption, figcaption, caption {
		font-style: italic;
		font-size: 90%;
	}
	.caption::before, figcaption::before, figcaption > .marker {
		font-weight: bold;
	}
	.caption, figcaption {
		counter-increment: figure;
	}

	/* DL list is indented 2em, but figure inside it is not */
	dd > .figure, dd > figure { margin-left: -2em }

/******************************************************************************/
/*                             Colored Boxes                                  */
/******************************************************************************/

	.issue, .note, .example, .assertion, .advisement, blockquote {
		padding: .5em;
		border: .5em;
		border-left-style: solid;
		page-break-inside: avoid;
	}
	span.issue, span.note {
		padding: .1em .5em .15em;
		border-right-style: solid;
	}

	.issue,
	.note,
	.example,
	.advisement,
	.assertion,
	blockquote {
		margin: 1em auto;
	}
	.note  > p:first-child,
	.issue > p:first-child,
	blockquote > :first-child {
		margin-top: 0;
	}
	blockquote > :last-child {
		margin-bottom: 0;
	}

/** Blockquotes ***************************************************************/

	blockquote {
		border-color: silver;
	}

/** Open issue ****************************************************************/

	.issue {
		border-color: #E05252;
		background: #FBE9E9;
		counter-increment: issue;
		overflow: auto;
	}
	.issue::before, .issue > .marker {
		text-transform: uppercase;
		color: #AE1E1E;
		padding-right: 1em;
		text-transform: uppercase;
	}
	/* Add .issue::before { content: "Issue " counter(issue) " "; } for autogen numbers,
	   or use class="marker" to mark up the issue number in source. */

/** Example *******************************************************************/

	.example {
		border-color: #E0CB52;
		background: #FCFAEE;
		counter-increment: example;
		overflow: auto;
		clear: both;
	}
	.example::before, .example > .marker {
		text-transform: uppercase;
		color: #827017;
		min-width: 7.5em;
		display: block;
	}
	/* Add .example::before { content: "Example " counter(example) " "; } for autogen numbers,
	   or use class="marker" to mark up the example number in source. */

/** Non-normative Note ********************************************************/

	.note {
		border-color: #52E052;
		background: #E9FBE9;
		overflow: auto;
	}

	.note::before, .note > .marker,
	details.note > summary::before,
	details.note > summary > .marker {
		text-transform: uppercase;
		display: block;
		color: hsl(120, 70%, 30%);
	}
	/* Add .note::before { content: "Note"; } for autogen label,
	   or use class="marker" to mark up the label in source. */

	details.note > summary {
		display: block;
		color: hsl(120, 70%, 30%);
	}
	details.note[open] > summary {
		border-bottom: 1px silver solid;
	}

/** Assertion Box *************************************************************/
	/*  for assertions in algorithms */

	.assertion {
		border-color: #AAA;
		background: #EEE;
	}

/** Advisement Box ************************************************************/
	/*  for attention-grabbing normative statements */

	.advisement {
		border-color: orange;
		border-style: none solid;
		background: #FFEECC;
	}
	strong.advisement {
		display: block;
		text-align: center;
	}
	.advisement > .marker {
		color: #B35F00;
	}

/** Spec Obsoletion Notice ****************************************************/
	/* obnoxious obsoletion notice for older/abandoned specs. */

	details {
		display: block;
	}
	summary {
		font-weight: bolder;
	}

	.annoying-warning:not(details),
	details.annoying-warning:not([open]) > summary,
	details.annoying-warning[open] {
		background: #fdd;
		color: red;
		font-weight: bold;
		padding: .75em 1em;
		border: thick red;
		border-style: solid;
		border-radius: 1em;
	}
	.annoying-warning :last-child {
		margin-bottom: 0;
	}

@media not print {
	details.annoying-warning[open] {
		position: fixed;
		left: 1em;
		right: 1em;
		bottom: 1em;
		z-index: 1000;
	}
}

	details.annoying-warning:not([open]) > summary {
		text-align: center;
	}

/** Entity Definition Boxes ***************************************************/

	.def {
		padding: .5em 1em;
		background: #DEF;
		margin: 1.2em 0;
		border-left: 0.5em solid #8CCBF2;
	}

/******************************************************************************/
/*                                    Tables                                  */
/******************************************************************************/

	th, td {
		text-align: left;
		text-align: start;
	}

/** Property/Descriptor Definition Tables *************************************/

	table.def {
		/* inherits .def box styling, see above */
		width: 100%;
		border-spacing: 0;
	}

	table.def td,
	table.def th {
		padding: 0.5em;
		vertical-align: baseline;
		border-bottom: 1px solid #bbd7e9;
	}

	table.def > tbody > tr:last-child th,
	table.def > tbody > tr:last-child td {
		border-bottom: 0;
	}

	table.def th {
		font-style: italic;
		font-weight: normal;
		padding-left: 1em;
		width: 3em;
	}

	/* For when values are extra-complex and need formatting for readability */
	table td.pre {
		white-space: pre-wrap;
	}

	/* A footnote at the bottom of a def table */
	table.def           td.footnote {
		padding-top: 0.6em;
	}
	table.def           td.footnote::before {
		content: " ";
		display: block;
		height: 0.6em;
		width: 4em;
		border-top: thin solid;
	}

/** Data tables (and properly marked-up index tables) *************************/
	/*
		 <table class="data"> highlights structural relationships in a table
		 when correct markup is used (e.g. thead/tbody, th vs. td, scope attribute)

		 Use class="complex data" for particularly complicated tables --
		 (This will draw more lines: busier, but clearer.)

		 Use class="long" on table cells with paragraph-like contents
		 (This will adjust text alignment accordingly.)
		 Alternately use class="longlastcol" on tables, to have the last column assume "long".
	*/

	table {
		word-wrap: normal;
		overflow-wrap: normal;
		hyphens: manual;
	}

	table.data,
	table.index {
		margin: 1em auto;
		border-collapse: collapse;
		border: hidden;
		width: 100%;
	}
	table.data caption,
	table.index caption {
		max-width: 50em;
		margin: 0 auto 1em;
	}

	table.data td,  table.data th,
	table.index td, table.index th {
		padding: 0.5em 1em;
		border-width: 1px;
		border-color: silver;
		border-top-style: solid;
	}

	table.data thead td:empty {
		padding: 0;
		border: 0;
	}

	table.data  thead,
	table.index thead,
	table.data  tbody,
	table.index tbody {
		border-bottom: 2px solid;
	}

	table.data colgroup,
	table.index colgroup {
		border-left: 2px solid;
	}

	table.data  tbody th:first-child,
	table.index tbody th:first-child  {
		border-right: 2px solid;
		border-top: 1px solid silver;
		padding-right: 1em;
	}

	table.data th[colspan],
	table.data td[colspan] {
		text-align: center;
	}

	table.complex.data th,
	table.complex.data td {
		border: 1px solid silver;
		text-align: center;
	}

	table.data.longlastcol td:last-child,
	table.data td.long {
	 vertical-align: baseline;
	 text-align: left;
	}

	table.data img {
		vertical-align: middle;
	}


/*
Alternate table alignment rules

	table.data,
	table.index {
		text-align: center;
	}

	table.data  thead th[scope="row"],
	table.index thead th[scope="row"] {
		text-align: right;
	}

	table.data  tbody th:first-child,
	table.index tbody th:first-child  {
		text-align: right;
	}

Possible extra rowspan handling

	table.data  tbody th[rowspan]:not([rowspan='1']),
	table.index tbody th[rowspan]:not([rowspan='1']),
	table.data  tbody td[rowspan]:not([rowspan='1']),
	table.index tbody td[rowspan]:not([rowspan='1']) {
		border-left: 1px solid silver;
	}

	table.data  tbody th[rowspan]:first-child,
	table.index tbody th[rowspan]:first-child,
	table.data  tbody td[rowspan]:first-child,
	table.index tbody td[rowspan]:first-child{
		border-left: 0;
		border-right: 1px solid silver;
	}
*/

/******************************************************************************/
/*                                  Indices                                   */
/******************************************************************************/


/** Table of Contents *********************************************************/

	.toc a {
		/* More spacing; use padding to make it part of the click target. */
		padding-top: 0.1rem;
		/* Larger, more consistently-sized click target */
		display: block;
		/* Reverse color scheme */
		color: black;
		border-color: #3980B5;
		border-bottom-width: 3px !important;
		margin-bottom: 0px !important;
	}
	.toc a:visited {
		border-color: #054572;
	}
	.toc a:not(:focus):not(:hover) {
		/* Allow colors to cascade through from link styling */
		border-bottom-color: transparent;
	}

	.toc, .toc ol, .toc ul, .toc li {
		list-style: none; /* Numbers must be inlined into source */
		/* because generated content isn't search/selectable and markers can't do multilevel yet */
		margin:  0;
		padding: 0;
		line-height: 1.1rem; /* consistent spacing */
	}

	/* ToC not indented until third level, but font style & margins show hierarchy */
	.toc > li             { font-weight: bold;   }
	.toc > li li          { font-weight: normal; }
	.toc > li li li       { font-size:   95%;    }
	.toc > li li li li    { font-size:   90%;    }
	.toc > li li li li .secno { font-size: 85%; }
	.toc > li li li li li { font-size:   85%;    }
	.toc > li li li li li .secno { font-size: 100%; }

	/* @supports not (display:grid) { */
		.toc > li             { margin: 1.5rem 0;    }
		.toc > li li          { margin: 0.3rem 0;    }
		.toc > li li li       { margin-left: 2rem;   }

		/* Section numbers in a column of their own */
		.toc .secno {
			float: left;
			width: 4rem;
			white-space: nowrap;
		}

		.toc li {
			clear: both;
		}

		:not(li) > .toc              { margin-left:  5rem; }
		.toc .secno                  { margin-left: -5rem; }
		.toc > li li li .secno       { margin-left: -7rem; }
		.toc > li li li li .secno    { margin-left: -9rem; }
		.toc > li li li li li .secno { margin-left: -11rem; }

		/* Tighten up indentation in narrow ToCs */
		@media (max-width: 30em) {
			:not(li) > .toc              { margin-left:  4rem; }
			.toc .secno                  { margin-left: -4rem; }
			.toc > li li li              { margin-left:  1rem; }
			.toc > li li li .secno       { margin-left: -5rem; }
			.toc > li li li li .secno    { margin-left: -6rem; }
			.toc > li li li li li .secno { margin-left: -7rem; }
		}
	/* } */

	@supports (display:grid) and (display:contents) {
		/* Use #toc over .toc to override non-@supports rules. */
		#toc {
			display: grid;
			align-content: start;
			grid-template-columns: auto 1fr;
			grid-column-gap: 1rem;
			column-gap: 1rem;
			grid-row-gap: .6rem;
			row-gap: .6rem;
		}
		#toc h2 {
			grid-column: 1 / -1;
			margin-bottom: 0;
		}
		#toc ol,
		#toc li,
		#toc a {
			display: contents;
			/* Switch <a> to subgrid when supported */
		}
		#toc span {
			margin: 0;
		}
		#toc > .toc > li > a > span {
			/* The spans of the top-level list,
			   comprising the first items of each top-level section. */
			margin-top: 1.1rem;
		}
		#toc#toc .secno { /* Ugh, need more specificity to override base.css */
			grid-column: 1;
			width: auto;
			margin-left: 0;
		}
		#toc .content {
			grid-column: 2;
			width: auto;
			margin-right: 1rem;
		}
		#toc .content:hover {
			background: rgba(75%, 75%, 75%, .25);
			border-bottom: 3px solid #054572;
			margin-bottom: -3px;
		}
		#toc li li li .content {
			margin-left: 1rem;
		}
		#toc li li li li .content {
			margin-left: 2rem;
		}
	}


/** Index *********************************************************************/

	/* Index Lists: Layout */
	ul.index       { margin-left: 0; columns: 15em; text-indent: 1em hanging; }
	ul.index li    { margin-left: 0; list-style: none; break-inside: avoid; }
	ul.index li li { margin-left: 1em }
	ul.index dl    { margin-top: 0; }
	ul.index dt    { margin: .2em 0 .2em 20px;}
	ul.index dd    { margin: .2em 0 .2em 40px;}
	/* Index Lists: Typography */
	ul.index ul,
	ul.index dl { font-size: smaller; }
	@media not print {
		ul.index li span {
			white-space: nowrap;
			color: transparent; }
		ul.index li a:hover + span,
		ul.index li a:focus + span {
			color: #707070;
		}
	}

/** Index Tables *****************************************************/
	/* See also the data table styling section, which this effectively subclasses */

	table.index {
		font-size: small;
		border-collapse: collapse;
		border-spacing: 0;
		text-align: left;
		margin: 1em 0;
	}

	table.index td,
	table.index th {
		padding: 0.4em;
	}

	table.index tr:hover td:not([rowspan]),
	table.index tr:hover th:not([rowspan]) {
		background: #f7f8f9;
	}

	/* The link in the first column in the property table (formerly a TD) */
	table.index th:first-child a {
		font-weight: bold;
	}

/******************************************************************************/
/*                                    Print                                   */
/******************************************************************************/

	@media print {
		/* Pages have their own margins. */
		html {
			margin: 0;
		}
		/* Serif for print. */
		body {
			font-family: serif;
		}
	}
	@page {
		margin: 1.5cm 1.1cm;
	}

/******************************************************************************/
/*                                    Legacy                                  */
/******************************************************************************/

	/* This rule is inherited from past style sheets. No idea what it's for. */
	.hide { display: none }



/******************************************************************************/
/*                             Overflow Control                               */
/******************************************************************************/

	.figure .caption, .sidefigure .caption, figcaption {
		/* in case figure is overlarge, limit caption to 50em */
		max-width: 50rem;
		margin-left: auto;
		margin-right: auto;
	}
	.overlarge {
		/* Magic to create good table positioning:
		   "content column" is 50ems wide at max; less on smaller screens.
		   Extra space (after ToC + content) is empty on the right.

		   1. When table < content column, centers table in column.
		   2. When content < table < available, left-aligns.
		   3. When table > available, fills available + scroll bar.
		*/ 
		display: grid;
		grid-template-columns: minmax(0, 50em);
	}
	.overlarge > table {
		/* limit preferred width of table */
		max-width: 50em;
		margin-left: auto;
		margin-right: auto;
	}

	@media (min-width: 55em) {
		.overlarge {
			margin-right: calc(13px + 26.5rem - 50vw);
			max-width: none;
		}
	}
	@media screen and (min-width: 78em) {
		body:not(.toc-inline) .overlarge {
			/* 30.5em body padding 50em content area */
			margin-right: calc(40em - 50vw) !important;
		}
	}
	@media screen and (min-width: 90em) {
		body:not(.toc-inline) .overlarge {
			/* 4em html margin 30.5em body padding 50em content area */
			margin-right: calc(84.5em - 100vw) !important;
		}
	}

	@media not print {
		.overlarge {
			overflow-x: auto;
			/* See Lea Verou's explanation background-attachment:
			 * http://lea.verou.me/2012/04/background-attachment-local/
			 *
			background: top left  / 4em 100% linear-gradient(to right,  #ffffff, rgba(255, 255, 255, 0)) local,
			            top right / 4em 100% linear-gradient(to left, #ffffff, rgba(255, 255, 255, 0)) local,
			            top left  / 1em 100% linear-gradient(to right,  #c3c3c5, rgba(195, 195, 197, 0)) scroll,
			            top right / 1em 100% linear-gradient(to left, #c3c3c5, rgba(195, 195, 197, 0)) scroll,
			            white;
			background-repeat: no-repeat;
			*/
		}
	}
</style>
  <link href="https://www.w3.org/StyleSheets/TR/2016/cg-draft" rel="stylesheet">
  <link href="https://wicg.github.io/import-maps/" rel="canonical">
<style>
.selected-text-file-an-issue {
  position: fixed;
  bottom: 0;
  right: 0;
  background: rgba(255, 255, 255, 0.8);
  font-size: smaller;
  padding: 4px 10px;
  z-index: 4;
}

summary {
  cursor: pointer;
}
</style>
<style>/* style-md-lists */

/* This is a weird hack for me not yet following the commonmark spec
   regarding paragraph and lists. */
[data-md] > :first-child {
    margin-top: 0;
}
[data-md] > :last-child {
    margin-bottom: 0;
}</style>
<style>/* style-selflinks */

.heading, .issue, .note, .example, li, dt {
    position: relative;
}
a.self-link {
    position: absolute;
    top: 0;
    left: calc(-1 * (3.5rem - 26px));
    width: calc(3.5rem - 26px);
    height: 2em;
    text-align: center;
    border: none;
    transition: opacity .2s;
    opacity: .5;
}
a.self-link:hover {
    opacity: 1;
}
.heading > a.self-link {
    font-size: 83%;
}
li > a.self-link {
    left: calc(-1 * (3.5rem - 26px) - 2em);
}
dfn > a.self-link {
    top: auto;
    left: auto;
    opacity: 0;
    width: 1.5em;
    height: 1.5em;
    background: gray;
    color: white;
    font-style: normal;
    transition: opacity .2s, background-color .2s, color .2s;
}
dfn:hover > a.self-link {
    opacity: 1;
}
dfn > a.self-link:hover {
    color: black;
}

a.self-link::before            { content: "¶"; }
.heading > a.self-link::before { content: "§"; }
dfn > a.self-link::before      { content: "#"; }</style>
<style>/* style-counters */

body {
    counter-reset: example figure issue;
}
.issue {
    counter-increment: issue;
}
.issue:not(.no-marker)::before {
    content: "Issue " counter(issue);
}

.example {
    counter-increment: example;
}
.example:not(.no-marker)::before {
    content: "Example " counter(example);
}
.invalid.example:not(.no-marker)::before,
.illegal.example:not(.no-marker)::before {
    content: "Invalid Example" counter(example);
}

figcaption {
    counter-increment: figure;
}
figcaption:not(.no-marker)::before {
    content: "Figure " counter(figure) " ";
}</style>
<style>/* style-var-click-highlighting */

    var { cursor: pointer; }
    var.selected0 { background-color: #F4D200; box-shadow: 0 0 0 2px #F4D200; }
    var.selected1 { background-color: #FF87A2; box-shadow: 0 0 0 2px #FF87A2; }
    var.selected2 { background-color: #96E885; box-shadow: 0 0 0 2px #96E885; }
    var.selected3 { background-color: #3EEED2; box-shadow: 0 0 0 2px #3EEED2; }
    var.selected4 { background-color: #EACFB6; box-shadow: 0 0 0 2px #EACFB6; }
    var.selected5 { background-color: #82DDFF; box-shadow: 0 0 0 2px #82DDFF; }
    var.selected6 { background-color: #FFBCF2; box-shadow: 0 0 0 2px #FFBCF2; }
    </style>
<style>/* style-autolinks */

.css.css, .property.property, .descriptor.descriptor {
    color: #005a9c;
    font-size: inherit;
    font-family: inherit;
}
.css::before, .property::before, .descriptor::before {
    content: "‘";
}
.css::after, .property::after, .descriptor::after {
    content: "’";
}
.property, .descriptor {
    /* Don't wrap property and descriptor names */
    white-space: nowrap;
}
.type { /* CSS value <type> */
    font-style: italic;
}
pre .property::before, pre .property::after {
    content: "";
}
[data-link-type="property"]::before,
[data-link-type="propdesc"]::before,
[data-link-type="descriptor"]::before,
[data-link-type="value"]::before,
[data-link-type="function"]::before,
[data-link-type="at-rule"]::before,
[data-link-type="selector"]::before,
[data-link-type="maybe"]::before {
    content: "‘";
}
[data-link-type="property"]::after,
[data-link-type="propdesc"]::after,
[data-link-type="descriptor"]::after,
[data-link-type="value"]::after,
[data-link-type="function"]::after,
[data-link-type="at-rule"]::after,
[data-link-type="selector"]::after,
[data-link-type="maybe"]::after {
    content: "’";
}

[data-link-type].production::before,
[data-link-type].production::after,
.prod [data-link-type]::before,
.prod [data-link-type]::after {
    content: "";
}

[data-link-type=element],
[data-link-type=element-attr] {
    font-family: Menlo, Consolas, "DejaVu Sans Mono", monospace;
    font-size: .9em;
}
[data-link-type=element]::before { content: "<" }
[data-link-type=element]::after  { content: ">" }

[data-link-type=biblio] {
    white-space: pre;
}</style>
<style>/* style-dfn-panel */

.dfn-panel {
    position: absolute;
    z-index: 35;
    height: auto;
    width: -webkit-fit-content;
    width: fit-content;
    max-width: 300px;
    max-height: 500px;
    overflow: auto;
    padding: 0.5em 0.75em;
    font: small Helvetica Neue, sans-serif, Droid Sans Fallback;
    background: #DDDDDD;
    color: black;
    border: outset 0.2em;
}
.dfn-panel:not(.on) { display: none; }
.dfn-panel * { margin: 0; padding: 0; text-indent: 0; }
.dfn-panel > b { display: block; }
.dfn-panel a { color: black; }
.dfn-panel a:not(:hover) { text-decoration: none !important; border-bottom: none !important; }
.dfn-panel > b + b { margin-top: 0.25em; }
.dfn-panel ul { padding: 0; }
.dfn-panel li { list-style: inside; }
.dfn-panel.activated {
    display: inline-block;
    position: fixed;
    left: .5em;
    bottom: 2em;
    margin: 0 auto;
    max-width: calc(100vw - 1.5em - .4em - .5em);
    max-height: 30vh;
}

.dfn-paneled { cursor: pointer; }
</style>
<style>/* style-syntax-highlighting */

.highlight:not(.idl) { background: hsl(24, 20%, 95%); }
code.highlight { padding: .1em; border-radius: .3em; }
pre.highlight, pre > code.highlight { display: block; padding: 1em; margin: .5em 0; overflow: auto; border-radius: 0; }
c-[a] { color: #990055 } /* Keyword.Declaration */
c-[b] { color: #990055 } /* Keyword.Type */
c-[c] { color: #708090 } /* Comment */
c-[d] { color: #708090 } /* Comment.Multiline */
c-[e] { color: #0077aa } /* Name.Attribute */
c-[f] { color: #669900 } /* Name.Tag */
c-[g] { color: #222222 } /* Name.Variable */
c-[k] { color: #990055 } /* Keyword */
c-[l] { color: #000000 } /* Literal */
c-[m] { color: #000000 } /* Literal.Number */
c-[n] { color: #0077aa } /* Name */
c-[o] { color: #999999 } /* Operator */
c-[p] { color: #999999 } /* Punctuation */
c-[s] { color: #a67f59 } /* Literal.String */
c-[t] { color: #a67f59 } /* Literal.String.Single */
c-[u] { color: #a67f59 } /* Literal.String.Double */
c-[cp] { color: #708090 } /* Comment.Preproc */
c-[c1] { color: #708090 } /* Comment.Single */
c-[cs] { color: #708090 } /* Comment.Special */
c-[kc] { color: #990055 } /* Keyword.Constant */
c-[kn] { color: #990055 } /* Keyword.Namespace */
c-[kp] { color: #990055 } /* Keyword.Pseudo */
c-[kr] { color: #990055 } /* Keyword.Reserved */
c-[ld] { color: #000000 } /* Literal.Date */
c-[nc] { color: #0077aa } /* Name.Class */
c-[no] { color: #0077aa } /* Name.Constant */
c-[nd] { color: #0077aa } /* Name.Decorator */
c-[ni] { color: #0077aa } /* Name.Entity */
c-[ne] { color: #0077aa } /* Name.Exception */
c-[nf] { color: #0077aa } /* Name.Function */
c-[nl] { color: #0077aa } /* Name.Label */
c-[nn] { color: #0077aa } /* Name.Namespace */
c-[py] { color: #0077aa } /* Name.Property */
c-[ow] { color: #999999 } /* Operator.Word */
c-[mb] { color: #000000 } /* Literal.Number.Bin */
c-[mf] { color: #000000 } /* Literal.Number.Float */
c-[mh] { color: #000000 } /* Literal.Number.Hex */
c-[mi] { color: #000000 } /* Literal.Number.Integer */
c-[mo] { color: #000000 } /* Literal.Number.Oct */
c-[sb] { color: #a67f59 } /* Literal.String.Backtick */
c-[sc] { color: #a67f59 } /* Literal.String.Char */
c-[sd] { color: #a67f59 } /* Literal.String.Doc */
c-[se] { color: #a67f59 } /* Literal.String.Escape */
c-[sh] { color: #a67f59 } /* Literal.String.Heredoc */
c-[si] { color: #a67f59 } /* Literal.String.Interpol */
c-[sx] { color: #a67f59 } /* Literal.String.Other */
c-[sr] { color: #a67f59 } /* Literal.String.Regex */
c-[ss] { color: #a67f59 } /* Literal.String.Symbol */
c-[vc] { color: #0077aa } /* Name.Variable.Class */
c-[vg] { color: #0077aa } /* Name.Variable.Global */
c-[vi] { color: #0077aa } /* Name.Variable.Instance */
c-[il] { color: #000000 } /* Literal.Number.Integer.Long */
</style>
 <body class="h-entry">
  <div class="head">
   <p data-fill-with="logo"></p>
   <h1 class="p-name no-ref" id="title">Import Maps</h1>
   <h2 class="no-num no-toc no-ref heading settled" id="subtitle"><span class="content">Draft Community Group Report, <time class="dt-updated" datetime="1970-01-01">1 January 1970</time></span></h2>
   <div data-fill-with="spec-metadata">
    <dl>
     <dt>This version:
     <dd><a class="u-url" href="https://wicg.github.io/import-maps/">https://wicg.github.io/import-maps/</a>
     <dt class="editor">Editor:
     <dd class="editor p-author h-card vcard"><a class="p-name fn u-url url" href="https://domenic.me/">Domenic Denicola</a> (<a class="p-org org" href="https://www.google.com/">Google</a>) <a class="u-email email" href="mailto:d@domenic.me">d@domenic.me</a>
     <dt>Participate:
     <dd><a href="https://github.com/WICG/import-maps">GitHub WICG/import-maps</a> (<a href="https://github.com/WICG/import-maps/issues/new">new issue</a>, <a href="https://github.com/WICG/import-maps/issues?state=open">open issues</a>)
     <dt>Commits:
     <dd><a href="https://github.com/WICG/import-maps/commits/master/spec.bs">GitHub spec.bs commits</a>
    </dl>
   </div>
   <div data-fill-with="warning"></div>
   <p class="copyright" data-fill-with="copyright"><a href="http://www.w3.org/Consortium/Legal/ipr-notice#Copyright">Copyright</a> © 1970 the Contributors to the Import Maps Specification, published by the <a href="https://www.w3.org/community/wicg/">Web Platform Incubator Community Group</a> under the <a href="https://www.w3.org/community/about/agreements/cla/">W3C Community Contributor License Agreement (CLA)</a>.
A human-readable <a href="http://www.w3.org/community/about/agreements/cla-deed/">summary</a> is available. </p>
   <hr title="Separator for header">
  </div>
  <div class="p-summary" data-fill-with="abstract">
   <h2 class="no-num no-toc no-ref heading settled" id="abstract"><span class="content">Abstract</span></h2>
   <p>Import maps allow web pages to control the behavior of JavaScript imports.</p>
  </div>
  <div data-fill-with="at-risk"></div>
  <h2 class="no-num no-toc no-ref heading settled" id="status"><span class="content">Status of this document</span></h2>
  <div data-fill-with="status">
   <p> This specification was published by the <a href="https://www.w3.org/community/wicg/">Web Platform Incubator Community Group</a>.
  It is not a W3C Standard nor is it on the W3C Standards Track.

  Please note that under the <a href="https://www.w3.org/community/about/agreements/cla/">W3C Community Contributor License Agreement (CLA)</a> there is a limited opt-out and other conditions apply.

  Learn more about <a href="http://www.w3.org/community/">W3C Community and Business Groups</a>. </p>
   <p></p>
  </div>
  <div data-fill-with="at-risk"></div>
  <nav data-fill-with="table-of-contents" id="toc">
   <h2 class="no-num no-toc no-ref" id="contents">Table of Contents</h2>
   <ol class="toc" role="directory">
    <li><a href="#definitions"><span class="secno">1</span> <span class="content">Definitions</span></a>
    <li>
     <a href="#acquiring"><span class="secno">2</span> <span class="content">Acquiring import maps</span></a>
     <ol class="toc">
      <li><a href="#integration-environment-settings-object"><span class="secno">2.1</span> <span class="content">New members of environment settings objects</span></a>
      <li><a href="#integration-script-type"><span class="secno">2.2</span> <span class="content">Script type</span></a>
      <li><a href="#integration-prepare-a-script"><span class="secno">2.3</span> <span class="content">Prepare a script</span></a>
      <li><a href="#integration-wait-for-import-maps"><span class="secno">2.4</span> <span class="content">Wait for import maps</span></a>
      <li><a href="#integration-register-an-import-map"><span class="secno">2.5</span> <span class="content">Registering an import map</span></a>
     </ol>
    <li><a href="#parsing"><span class="secno">3</span> <span class="content">Parsing import maps</span></a>
    <li>
     <a href="#resolving"><span class="secno">4</span> <span class="content">Resolving module specifiers</span></a>
     <ol class="toc">
      <li><a href="#new-resolve-algorithm"><span class="secno">4.1</span> <span class="content">New "resolve a module specifier"</span></a>
      <li><a href="#resolving-updates"><span class="secno">4.2</span> <span class="content">Updates to other algorithms</span></a>
     </ol>
    <li>
     <a href="#security-and-privacy"><span class="secno">5</span> <span class="content">Security and Privacy</span></a>
     <ol class="toc">
      <li>
       <a href="#threat-models"><span class="secno">5.1</span> <span class="content">Threat models</span></a>
       <ol class="toc">
        <li><a href="#comparison-with-first-party-scripts"><span class="secno">5.1.1</span> <span class="content">Comparison with first-party scripts</span></a>
        <li><a href="#comparison-with-service-workers"><span class="secno">5.1.2</span> <span class="content">Comparison with Service Workers</span></a>
        <li><a href="#complexity"><span class="secno">5.1.3</span> <span class="content">Time/memory complexity</span></a>
       </ol>
      <li><a href="#note-on-import-specifiers"><span class="secno">5.2</span> <span class="content">A note on import specifiers</span></a>
     </ol>
    <li>
     <a href="#index"><span class="secno"></span> <span class="content">Index</span></a>
     <ol class="toc">
      <li><a href="#index-defined-here"><span class="secno"></span> <span class="content">Terms defined by this specification</span></a>
      <li><a href="#index-defined-elsewhere"><span class="secno"></span> <span class="content">Terms defined by reference</span></a>
     </ol>
    <li>
     <a href="#references"><span class="secno"></span> <span class="content">References</span></a>
     <ol class="toc">
      <li><a href="#normative"><span class="secno"></span> <span class="content">Normative References</span></a>
     </ol>
    <li><a href="#issues-index"><span class="secno"></span> <span class="content">Issues Index</span></a>
   </ol>
  </nav>
  <main>
<script async src="https://resources.whatwg.org/file-issue.js"></script>
   <h2 class="heading settled" data-level="1" id="definitions"><span class="secno">1. </span><span class="content">Definitions</span><a class="self-link" href="#definitions"></a></h2>
   <p>A <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="specifier-map">specifier map</dfn> is an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map">ordered map</a> from <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string">strings</a> to <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url">URLs</a>.</p>
   <p>A <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="import-map">import map</dfn> is a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#struct" id="ref-for-struct">struct</a> with two <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#struct-item" id="ref-for-struct-item">items</a>:</p>
   <ul>
    <li data-md>
     <p><dfn class="dfn-paneled" data-dfn-for="import map" data-dfn-type="dfn" data-noexport id="import-map-imports">imports</dfn>, a <a data-link-type="dfn" href="#specifier-map" id="ref-for-specifier-map">specifier map</a>, and</p>
    <li data-md>
     <p><dfn class="dfn-paneled" data-dfn-for="import map" data-dfn-type="dfn" data-noexport id="import-map-scopes">scopes</dfn>, an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map①">ordered map</a> of <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url①">URLs</a> to <a data-link-type="dfn" href="#specifier-map" id="ref-for-specifier-map①">specifier maps</a>.</p>
   </ul>
   <p>An <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="empty-import-map">empty import map</dfn> is an <a data-link-type="dfn" href="#import-map" id="ref-for-import-map">import map</a> with its <a data-link-type="dfn" href="#import-map-imports" id="ref-for-import-map-imports">imports</a> and <a data-link-type="dfn" href="#import-map-scopes" id="ref-for-import-map-scopes">scopes</a> both being empty maps.</p>
   <h2 class="heading settled" data-level="2" id="acquiring"><span class="secno">2. </span><span class="content">Acquiring import maps</span><a class="self-link" href="#acquiring"></a></h2>
   <h3 class="heading settled" data-level="2.1" id="integration-environment-settings-object"><span class="secno">2.1. </span><span class="content">New members of environment settings objects</span><a class="self-link" href="#integration-environment-settings-object"></a></h3>
   <p>Each <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#environment-settings-object" id="ref-for-environment-settings-object">environment settings object</a> will get an <dfn class="dfn-paneled" data-dfn-for="environment settings object" data-dfn-type="dfn" data-noexport id="environment-settings-object-import-map">import map</dfn> algorithm, which returns an <a data-link-type="dfn" href="#import-map" id="ref-for-import-map①">import map</a> created by the first <code>&lt;script type="importmap"></code> element that is encountered (before the cutoff).</p>
   <p>A <code class="idl"><a data-link-type="idl" href="https://dom.spec.whatwg.org/#document" id="ref-for-document">Document</a></code> has an <a data-link-type="dfn" href="#import-map" id="ref-for-import-map②">import map</a> <dfn class="dfn-paneled" data-dfn-for="Document" data-dfn-type="dfn" data-noexport id="document-import-map">import map</dfn>. It is initially a new <a data-link-type="dfn" href="#empty-import-map" id="ref-for-empty-import-map">empty import map</a>.</p>
   <p>In <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/window-object.html#set-up-a-window-environment-settings-object" id="ref-for-set-up-a-window-environment-settings-object">set up a window environment settings object</a>, <var>settings object</var>’s <a data-link-type="dfn" href="#environment-settings-object-import-map" id="ref-for-environment-settings-object-import-map">import map</a> returns the <a data-link-type="dfn" href="#document-import-map" id="ref-for-document-import-map">import map</a> of <var>window</var>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/window-object.html#concept-document-window" id="ref-for-concept-document-window">associated <code>Document</code></a>.</p>
   <p>A <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope" id="ref-for-workerglobalscope">WorkerGlobalScope</a></code> has an <a data-link-type="dfn" href="#import-map" id="ref-for-import-map③">import map</a> <dfn class="dfn-paneled" data-dfn-for="WorkerGlobalScope" data-dfn-type="dfn" data-noexport id="workerglobalscope-import-map">import map</dfn>. It is initially a new <a data-link-type="dfn" href="#empty-import-map" id="ref-for-empty-import-map①">empty import map</a>.</p>
   <p class="issue" id="issue-53aae9a6"><a class="self-link" href="#issue-53aae9a6"></a> Specify a way to set <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope" id="ref-for-workerglobalscope①">WorkerGlobalScope</a></code>'s <a data-link-type="dfn" href="#workerglobalscope-import-map" id="ref-for-workerglobalscope-import-map">import map</a>. We might want to inherit parent context’s import maps, or provide APIs on <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope" id="ref-for-workerglobalscope②">WorkerGlobalScope</a></code>, but we are not sure. Currently it is always an <a data-link-type="dfn" href="#empty-import-map" id="ref-for-empty-import-map②">empty import map</a>. See <a href="https://github.com/WICG/import-maps/issues/2">#2</a>.</p>
   <p></p>
   <p>In <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/workers.html#set-up-a-worker-environment-settings-object" id="ref-for-set-up-a-worker-environment-settings-object">set up a worker environment settings object</a>, <var>settings object</var>’s <a data-link-type="dfn" href="#environment-settings-object-import-map" id="ref-for-environment-settings-object-import-map①">import map</a> returns <var>worker global scope</var>’s <a data-link-type="dfn" href="#workerglobalscope-import-map" id="ref-for-workerglobalscope-import-map①">import map</a>.</p>
   <p class="note" role="note"> This infrastructure is very similar to the existing specification for module maps. </p>
   <p>A <code class="idl"><a data-link-type="idl" href="https://dom.spec.whatwg.org/#document" id="ref-for-document①">Document</a></code> has a <dfn class="dfn-paneled" data-dfn-for="Document" data-dfn-type="dfn" data-noexport id="document-pending-import-map-script">pending import map script</dfn>, which is a <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/scripting.html#htmlscriptelement" id="ref-for-htmlscriptelement">HTMLScriptElement</a></code> or null, initially null.</p>
   <p class="note" role="note">This is modified by <a href="#integration-prepare-a-script">§ 2.3 Prepare a script</a>.</p>
   <p>Each <code class="idl"><a data-link-type="idl" href="https://dom.spec.whatwg.org/#document" id="ref-for-document②">Document</a></code> has an <dfn class="dfn-paneled" data-dfn-for="Document" data-dfn-type="dfn" data-noexport id="document-acquiring-import-maps">acquiring import maps</dfn> boolean. It is initially true.</p>
   <div class="note" role="note">
     These two pieces of state are used to achieve the following behavior: 
    <ul>
     <li>An import map is accepted if and only if it is added (i.e., its corresponding <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/scripting.html#script" id="ref-for-script">script</a></code> element is added) before the first module load is started, even if the loading of the import map file doesn’t finish before the first module load is started. 
     <li>Module loading waits for any import map that has already started loading. 
    </ul>
   </div>
   <h3 class="heading settled" data-level="2.2" id="integration-script-type"><span class="secno">2.2. </span><span class="content">Script type</span><a class="self-link" href="#integration-script-type"></a></h3>
   <p>To process import maps in the <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script">prepare a script</a> algorithm consistently with existing script types (i.e. classic or module), we make the following changes:</p>
   <ul>
    <li data-md>
     <p>Introduce <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="import-map-parse-result">import map parse result</dfn>, which is a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#struct" id="ref-for-struct①">struct</a> with three <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#struct-item" id="ref-for-struct-item①">items</a>:</p>
     <ul>
      <li data-md>
       <p>a <dfn class="dfn-paneled" data-dfn-for="import map parse result" data-dfn-type="dfn" data-noexport id="import-map-parse-result-settings-object">settings object</dfn>, an <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#environment-settings-object" id="ref-for-environment-settings-object①">environment settings object</a>;</p>
      <li data-md>
       <p>an <dfn class="dfn-paneled" data-dfn-for="import map parse result" data-dfn-type="dfn" data-noexport id="import-map-parse-result-import-map">import map</dfn>, an <a data-link-type="dfn" href="#import-map" id="ref-for-import-map④">import map</a>; and</p>
      <li data-md>
       <p>an <dfn class="dfn-paneled" data-dfn-for="import map parse result" data-dfn-type="dfn" data-noexport id="import-map-parse-result-error-to-rethrow">error to rethrow</dfn>, a JavaScript value representing a parse error when non-null.</p>
     </ul>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-type" id="ref-for-concept-script-type">the script’s type</a> should be either "<code>classic</code>", "<code>module</code>", or "<code>importmap</code>".</p>
    <li data-md>
     <p>Rename <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-script" id="ref-for-concept-script-script">the script’s script</a> to <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="the-scripts-result">the script’s result</dfn>, which can be either a <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script" id="ref-for-concept-script">script</a> or an <a data-link-type="dfn" href="#import-map-parse-result" id="ref-for-import-map-parse-result">import map parse result</a>.</p>
   </ul>
   <p>The following algorithms are updated accordingly:</p>
   <ul>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script①">prepare a script</a>: see <a href="#integration-prepare-a-script">§ 2.3 Prepare a script</a>.</p>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#execute-the-script-block" id="ref-for-execute-the-script-block">execute a script block</a> Step 4: add the following case.</p>
     <dl>
      <dt>"<code>importmap</code>"
      <dd>
       <ol>
        <li data-md>
         <p class="assertion">Assert: Never reached.</p>
         <p class="note" role="note">Import maps are processed by <a data-link-type="dfn" href="#register-an-import-map" id="ref-for-register-an-import-map">register an import map</a> instead of <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#execute-the-script-block" id="ref-for-execute-the-script-block①">execute a script block</a>.</p>
       </ol>
     </dl>
   </ul>
   <p class="note" role="note">Because we don’t make <a data-link-type="dfn" href="#import-map-parse-result" id="ref-for-import-map-parse-result①">import map parse result</a> the new subclass of <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script" id="ref-for-concept-script①">script</a>, other script execution-related specs are left unaffected.</p>
   <h3 class="heading settled" data-level="2.3" id="integration-prepare-a-script"><span class="secno">2.3. </span><span class="content">Prepare a script</span><a class="self-link" href="#integration-prepare-a-script"></a></h3>
   <p>Inside the <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script②">prepare a script</a> algorithm, we make the following changes:</p>
   <ul>
    <li data-md>
     <p>Insert the following step to <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script③">prepare a script</a> step 7, under "Determine the script’s type as follows:":</p>
     <ul>
      <li data-md>
       <p>If the script block’s type string is an <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ascii-case-insensitive" id="ref-for-ascii-case-insensitive">ASCII case-insensitive</a> match for the string "<code>importmap</code>", <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-type" id="ref-for-concept-script-type①">the script’s type</a> is "<code>importmap</code>".</p>
     </ul>
    <li data-md>
     <p>Insert the following step before <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script④">prepare a script</a> step 24:</p>
     <ul>
      <li data-md>
       <p>If <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-type" id="ref-for-concept-script-type②">the script’s type</a> is "<code>importmap</code>", and either the element’s <a data-link-type="dfn" href="https://dom.spec.whatwg.org/#concept-node-document" id="ref-for-concept-node-document">node document</a>'s <a data-link-type="dfn" href="#document-acquiring-import-maps" id="ref-for-document-acquiring-import-maps">acquiring import maps</a> is false or the element’s <a data-link-type="dfn" href="https://dom.spec.whatwg.org/#concept-node-document" id="ref-for-concept-node-document①">node document</a>'s <a data-link-type="dfn" href="#document-pending-import-map-script" id="ref-for-document-pending-import-map-script">pending import map script</a> is non-null, then <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#queue-a-task" id="ref-for-queue-a-task">queue a task</a> to <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/infrastructure.html#concept-event-fire" id="ref-for-concept-event-fire">fire an event</a> named <code>error</code> at the element, and return.</p>
       <p class="note" role="note">In the future we could losen the constrain of erroring when the <a data-link-type="dfn" href="#document-pending-import-map-script" id="ref-for-document-pending-import-map-script①">pending import map script</a> is non-null, to allow multiple import maps.</p>
     </ul>
    <li data-md>
     <p>Insert the following case to <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script⑤">prepare a script</a> step 24.6:</p>
     <dl>
      <dt>"<code>importmap</code>"
      <dd> <a data-link-type="dfn" href="#fetch-an-import-map" id="ref-for-fetch-an-import-map">Fetch an import map</a> given <var>url</var>, <var>settings object</var>, and <var>options</var>. 
     </dl>
    <li data-md>
     <p>Insert the following case to <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script⑥">prepare a script</a> step 25.2:</p>
     <dl>
      <dt>"<code>importmap</code>"
      <dd>
       <ol>
        <li data-md>
         <p>Let <var>import map parse result</var> be the result of <a data-link-type="dfn" href="#create-an-import-map-parse-result" id="ref-for-create-an-import-map-parse-result">create an import map parse result</a>, given <var>source text</var>, <var>base URL</var> and <var>settings object</var>.</p>
        <li data-md>
         <p>Set <a data-link-type="dfn" href="#the-scripts-result" id="ref-for-the-scripts-result">the script’s result</a> to <var>import map parse result</var>.</p>
        <li data-md>
         <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#the-script-is-ready" id="ref-for-the-script-is-ready">The script is ready</a>.</p>
       </ol>
     </dl>
    <li data-md>
     <p>Insert the following case to <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script⑦">prepare a script</a> step 26:</p>
     <dl>
      <dt>If <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-type" id="ref-for-concept-script-type③">the script’s type</a> is "<code>importmap</code>"
      <dd>
        Set the element’s <a data-link-type="dfn" href="https://dom.spec.whatwg.org/#concept-node-document" id="ref-for-concept-node-document②">node document</a>'s <a data-link-type="dfn" href="#document-pending-import-map-script" id="ref-for-document-pending-import-map-script②">pending import map script</a> to the element.
    When <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#the-script-is-ready" id="ref-for-the-script-is-ready①">the script is ready</a>, run the following steps: 
       <ol>
        <li data-md>
         <p><a data-link-type="dfn" href="#register-an-import-map" id="ref-for-register-an-import-map①">Register an import map</a> given the <a data-link-type="dfn" href="#document-pending-import-map-script" id="ref-for-document-pending-import-map-script③">pending import map script</a>.</p>
        <li data-md>
         <p>Set the <a data-link-type="dfn" href="#document-pending-import-map-script" id="ref-for-document-pending-import-map-script④">pending import map script</a> to null.</p>
         <p class="note" role="note">This will (asynchronously) unblock any <a data-link-type="dfn" href="#wait-for-import-maps" id="ref-for-wait-for-import-maps">wait for import maps</a> algorithm instances.</p>
       </ol>
     </dl>
   </ul>
   <p class="note" role="note"> This is specified similar to the <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#list-of-scripts-that-will-execute-in-order-as-soon-as-possible" id="ref-for-list-of-scripts-that-will-execute-in-order-as-soon-as-possible">list of scripts that will execute in order as soon as possible</a>. </p>
   <p class="note" role="note"> CSPs are applied to inline import maps at Step 13 of <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script" id="ref-for-prepare-a-script⑧">prepare a script</a>, and to external import maps in <a data-link-type="dfn" href="#fetch-an-import-map" id="ref-for-fetch-an-import-map①">fetch an import map</a>, just like applied to classic/module scripts. </p>
   <div class="algorithm" data-algorithm="fetch an import map">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="fetch-an-import-map">fetch an import map</dfn> given <var>url</var>, <var>settings object</var>, and <var>options</var>, run the following steps. This algorithm asynchronously returns an <a data-link-type="dfn" href="#import-map" id="ref-for-import-map⑤">import map</a> or null. 
    <p class="note" role="note">This algorithm is specified consistently with <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-single-module-script" id="ref-for-fetch-a-single-module-script">fetch a single module script</a> steps 5, 7, 8, 9, 10, and 12.1. Particularly, we enforce CORS to avoid leaking the import map contents that shouldn’t be accessed.</p>
    <ol>
     <li data-md>
      <p>Let <var>request</var> be a new <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request" id="ref-for-concept-request">request</a> whose <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request-url" id="ref-for-concept-request-url">url</a> is <var>url</var>, <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request-destination" id="ref-for-concept-request-destination">destination</a> is "<code>script</code>", <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request-mode" id="ref-for-concept-request-mode">mode</a> is "<code>cors</code>", <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request-referrer" id="ref-for-concept-request-referrer">referrer</a> is "<code>client</code>", and <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request-client" id="ref-for-concept-request-client">client</a> is <var>settings object</var>.</p>
      <p class="note" role="note">Here we use "<code>script</code>" as the <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-request-destination" id="ref-for-concept-request-destination①">destination</a>, which means the <code>script-src-elem</code> CSP directive applies.</p>
     <li data-md>
      <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#set-up-the-module-script-request" id="ref-for-set-up-the-module-script-request">Set up the module script request</a> given <var>request</var> and <var>options</var>.</p>
     <li data-md>
      <p><a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-fetch" id="ref-for-concept-fetch">Fetch</a> <var>request</var>. Return from this algorithm, and run the remaining steps as part of the fetch’s <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#process-response" id="ref-for-process-response">process response</a> for the <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response" id="ref-for-concept-response">response</a> <var>response</var>.</p>
      <p class="note" role="note"><var>response</var> is always <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/urls-and-fetching.html#cors-same-origin" id="ref-for-cors-same-origin">CORS-same-origin</a>.</p>
     <li data-md>
      <p>If any of the following conditions are met, asynchronously complete this algorithm with null, and abort these steps:</p>
      <ul>
       <li data-md>
        <p><var>response</var>’s <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response-type" id="ref-for-concept-response-type">type</a> is "<code>error</code>"</p>
       <li data-md>
        <p><var>response</var>’s <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response-status" id="ref-for-concept-response-status">status</a> is not an <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#ok-status" id="ref-for-ok-status">ok status</a></p>
       <li data-md>
        <p>The result of <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-header-extract-mime-type" id="ref-for-concept-header-extract-mime-type">extracting a MIME type</a> from <var>response</var>’s <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response-header-list" id="ref-for-concept-response-header-list">header list</a> is not <code>"application/importmap+json"</code></p>
        <p class="note" role="note">For more context on MIME type checking, see <a href="https://github.com/WICG/import-maps/issues/105">#105</a> and <a href="https://github.com/WICG/import-maps/pull/119">#119</a>.</p>
      </ul>
     <li data-md>
      <p>Let <var>source text</var> be the result of <a data-link-type="dfn" href="https://encoding.spec.whatwg.org/#utf-8-decode" id="ref-for-utf-8-decode">UTF-8 decoding</a> response’s <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response-body" id="ref-for-concept-response-body">body</a>.</p>
     <li data-md>
      <p>Asynchronously complete this algorithm with the result of <a data-link-type="dfn" href="#create-an-import-map-parse-result" id="ref-for-create-an-import-map-parse-result①">create an import map parse result</a>, given <var>source text</var>, <var>response</var>’s <a data-link-type="dfn" href="https://fetch.spec.whatwg.org/#concept-response-url" id="ref-for-concept-response-url">url</a>, and <var>settings object</var>.</p>
    </ol>
   </div>
   <h3 class="heading settled" data-level="2.4" id="integration-wait-for-import-maps"><span class="secno">2.4. </span><span class="content">Wait for import maps</span><a class="self-link" href="#integration-wait-for-import-maps"></a></h3>
   <div class="algorithm" data-algorithm="wait for import maps">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="wait-for-import-maps">wait for import maps</dfn> given <var>settings object</var>: 
    <ol>
     <li data-md>
      <p>If <var>settings object</var>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-settings-object-global" id="ref-for-concept-settings-object-global">global object</a> is a <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/window-object.html#window" id="ref-for-window">Window</a></code> object:</p>
      <ol>
       <li data-md>
        <p>Let <var>document</var> be <var>settings object</var>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-settings-object-global" id="ref-for-concept-settings-object-global①">global object</a>'s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/window-object.html#concept-document-window" id="ref-for-concept-document-window①">associated <code>Document</code></a>.</p>
       <li data-md>
        <p>Set <var>document</var>’s <a data-link-type="dfn" href="#document-acquiring-import-maps" id="ref-for-document-acquiring-import-maps①">acquiring import maps</a> to false.</p>
       <li data-md>
        <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#spin-the-event-loop" id="ref-for-spin-the-event-loop">Spin the event loop</a> until <var>document</var>’s <a data-link-type="dfn" href="#document-pending-import-map-script" id="ref-for-document-pending-import-map-script⑤">pending import map script</a> is null.</p>
      </ol>
     <li data-md>
      <p>Asynchronously complete this algorithm.</p>
    </ol>
    <p class="note" role="note">No actions are specified for <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope" id="ref-for-workerglobalscope③">WorkerGlobalScope</a></code> because for now there are no mechanisms for adding import maps to <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope" id="ref-for-workerglobalscope④">WorkerGlobalScope</a></code>.</p>
   </div>
   <p>Insert a call to <a data-link-type="dfn" href="#wait-for-import-maps" id="ref-for-wait-for-import-maps①">wait for import maps</a> at the beginning of the following HTML spec concepts.</p>
   <ul>
    <li data-md>
     <p><a data-link-type="dfn">fetch an external module script graph</a></p>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-an-import()-module-script-graph" id="ref-for-fetch-an-import()-module-script-graph">fetch an import() module script graph</a></p>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-modulepreload-module-script-graph" id="ref-for-fetch-a-modulepreload-module-script-graph">fetch a modulepreload module script graph</a></p>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-an-inline-module-script-graph" id="ref-for-fetch-an-inline-module-script-graph">fetch an inline module script graph</a></p>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-module-worker-script-tree" id="ref-for-fetch-a-module-worker-script-tree">fetch a module worker script graph</a> (using <var>module map settings object</var>)</p>
   </ul>
   <div class="advisement">
     In this draft of the spec, which inserts itself into these HTML concepts, the settings object used here is the <var>module map settings object</var>, not <var>fetch client settings object</var>, because <a data-link-type="dfn" href="#resolve-a-module-specifier" id="ref-for-resolve-a-module-specifier">resolve a module specifier</a> uses the import map of <var>module map settings object</var>. In a potential future version of the import maps infrastructure, which interjects itself at the layer of the Fetch spec in order to support <code>import:</code> URLs, we would instead use <var>fetch client settings object</var>. 
    <p>This only affects <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-module-worker-script-tree" id="ref-for-fetch-a-module-worker-script-tree①">fetch a module worker script graph</a>, where these two settings objects are different. And, given that the import maps for <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope" id="ref-for-workerglobalscope⑤">WorkerGlobalScope</a></code>s are currently always empty, the only fetch that could be impacted is that of the initial module. But even that would not be impacted, because that fetch is done using URLs, not specifiers. So this is not a future compatibility hazard, just something to keep in mind as we develop import maps in module workers.</p>
   </div>
   <div class="advisement">
     Depending on the exact location of <a data-link-type="dfn" href="#wait-for-import-maps" id="ref-for-wait-for-import-maps②">wait for import maps</a>, <code>import(unresolvableSpecifier)</code> might behave differently between a HTML-spec- and Fetch-spec-based import maps. In particular, in the current draft, <a data-link-type="dfn" href="#document-acquiring-import-maps" id="ref-for-document-acquiring-import-maps②">acquiring import maps</a> is set to false after an <code>import()</code>-initiated failure to <a data-link-type="dfn" href="#resolve-a-module-specifier" id="ref-for-resolve-a-module-specifier①">resolve a module specifier</a>, thus causing any later-encountered import maps to cause an <code>error</code> event instead of being processed. Whereas, if <a data-link-type="dfn" href="#wait-for-import-maps" id="ref-for-wait-for-import-maps③">wait for import maps</a> was called as part of the Fetch spec, it’s possible it would be natural to specify things such that <a data-link-type="dfn" href="#document-acquiring-import-maps" id="ref-for-document-acquiring-import-maps③">acquiring import maps</a> remains true (as it does for cases like <code>&lt;script type="module" src="http://:invalidurl"></code>). 
    <p>This should not be much of a compatibility hazard, as it only makes esoteric error cases into successes. And we can always preserve the behavior as specced here if necessary, with some potential additional complexity.</p>
   </div>
   <h3 class="heading settled" data-level="2.5" id="integration-register-an-import-map"><span class="secno">2.5. </span><span class="content">Registering an import map</span><a class="self-link" href="#integration-register-an-import-map"></a></h3>
   <div class="algorithm" data-algorithm="register an import map">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="register-an-import-map">register an import map</dfn> given an <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/scripting.html#htmlscriptelement" id="ref-for-htmlscriptelement①">HTMLScriptElement</a></code> <var>element</var>: 
    <ol>
     <li data-md>
      <p>If <var>element</var>’s <a data-link-type="dfn" href="#the-scripts-result" id="ref-for-the-scripts-result①">the script’s result</a> is null, then <a data-link-type="dfn" href="https://dom.spec.whatwg.org/#concept-event-fire" id="ref-for-concept-event-fire①">fire an event</a> named <code>error</code> at <var>element</var>, and return.</p>
     <li data-md>
      <p>Let <var>import map parse result</var> be <var>element</var>’s <a data-link-type="dfn" href="#the-scripts-result" id="ref-for-the-scripts-result②">the script’s result</a>.</p>
     <li data-md>
      <p class="assertion">Assert: <var>element</var>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-type" id="ref-for-concept-script-type④">the script’s type</a> is "<code>importmap</code>".</p>
     <li data-md>
      <p class="assertion">Assert: <var>import map parse result</var> is an <a data-link-type="dfn" href="#import-map-parse-result" id="ref-for-import-map-parse-result②">import map parse result</a>.</p>
     <li data-md>
      <p>Let <var>settings object</var> be <var>import map parse result</var>’s <a data-link-type="dfn" href="#import-map-parse-result-settings-object" id="ref-for-import-map-parse-result-settings-object">settings object</a>.</p>
     <li data-md>
      <p>If <var>element</var>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/infrastructure.html#node-document" id="ref-for-node-document">node document</a>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#relevant-settings-object" id="ref-for-relevant-settings-object">relevant settings object</a> is not equal to <var>settings object</var>, then return.</p>
      <p class="note" role="note">This is spec’ed consistently with <a href="https://github.com/whatwg/html/pull/2673">whatwg/html#2673</a>.</p>
      <p class="advisement">Currently we don’t fire <code>error</code> events in this case. If we change the decision at <a href="https://github.com/whatwg/html/pull/2673">whatwg/html#2673</a> to fire <code>error</code> events, then we should change this step accordingly.</p>
     <li data-md>
      <p>If <var>import map parse result</var>’s <a data-link-type="dfn" href="#import-map-parse-result-error-to-rethrow" id="ref-for-import-map-parse-result-error-to-rethrow">error to rethrow</a> is not null, then:</p>
      <ol>
       <li data-md>
        <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#report-the-exception" id="ref-for-report-the-exception">Report the exception</a> given <var>import map parse result</var>’s <a data-link-type="dfn" href="#import-map-parse-result-error-to-rethrow" id="ref-for-import-map-parse-result-error-to-rethrow①">error to rethrow</a>.</p>
        <p class="issue" id="issue-3b40327d"><a class="self-link" href="#issue-3b40327d"></a>There are no relevant <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script" id="ref-for-concept-script②">script</a>, because <a data-link-type="dfn" href="#import-map-parse-result" id="ref-for-import-map-parse-result③">import map parse result</a> isn’t a <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script" id="ref-for-concept-script③">script</a>. This needs to wait for <a href="https://github.com/whatwg/html/issues/958">whatwg/html#958</a> before it is fixable.</p>
       <li data-md>
        <p>Return.</p>
      </ol>
     <li data-md>
      <p>Set <var>element</var>’s <a data-link-type="dfn" href="https://dom.spec.whatwg.org/#concept-node-document" id="ref-for-concept-node-document③">node document</a>'s <a data-link-type="dfn" href="#document-import-map" id="ref-for-document-import-map①">import map</a> to <var>import map parse result</var>’s <a data-link-type="dfn" href="#import-map-parse-result-import-map" id="ref-for-import-map-parse-result-import-map">import map</a>.</p>
     <li data-md>
      <p>If <var>element</var> is <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-external" id="ref-for-concept-script-external">from an external file</a>, then <a data-link-type="dfn" href="https://dom.spec.whatwg.org/#concept-event-fire" id="ref-for-concept-event-fire②">fire an event</a> named <code>load</code> at <var>element</var>.</p>
    </ol>
    <p class="note" role="note"> The timing of <a data-link-type="dfn" href="#register-an-import-map" id="ref-for-register-an-import-map②">register an import map</a> is observable by possible <code>error</code> and <code>load</code> events, or by the fact that after <a data-link-type="dfn" href="#register-an-import-map" id="ref-for-register-an-import-map③">register an import map</a> an import map <code><a data-link-type="element" href="https://html.spec.whatwg.org/multipage/scripting.html#script" id="ref-for-script①">script</a></code> can be moved to another <code class="idl"><a data-link-type="idl" href="https://dom.spec.whatwg.org/#document" id="ref-for-document③">Document</a></code>. On the other hand, the updated <a data-link-type="dfn" href="#document-import-map" id="ref-for-document-import-map②">import map</a> is not observable until <a data-link-type="dfn" href="#wait-for-import-maps" id="ref-for-wait-for-import-maps④">wait for import maps</a> completes. </p>
   </div>
   <h2 class="heading settled" data-level="3" id="parsing"><span class="secno">3. </span><span class="content">Parsing import maps</span><a class="self-link" href="#parsing"></a></h2>
   <div class="algorithm" data-algorithm="parse an import map string">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-lt="parse an import map string|parsing an import map string" data-noexport id="parse-an-import-map-string">parse an import map string</dfn>, given a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string①">string</a> <var>input</var> and a <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url②">URL</a> <var>baseURL</var>: 
    <ol>
     <li data-md>
      <p>Let <var>parsed</var> be the result of <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#parse-json-into-infra-values" id="ref-for-parse-json-into-infra-values">parsing JSON into Infra values</a> given <var>input</var>.</p>
     <li data-md>
      <p>If <var>parsed</var> is not a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map②">map</a>, then throw a <code class="idl"><a data-link-type="idl" href="https://heycam.github.io/webidl/#exceptiondef-typeerror" id="ref-for-exceptiondef-typeerror">TypeError</a></code> indicating that the top-level value must be a JSON object.</p>
     <li data-md>
      <p>Let <var>sortedAndNormalizedImports</var> be an empty <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map③">map</a>.</p>
     <li data-md>
      <p>If <var>parsed</var>["<code>imports</code>"] <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-exists" id="ref-for-map-exists">exists</a>, then:</p>
      <ol>
       <li data-md>
        <p>If <var>parsed</var>["<code>imports</code>"] is not a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map④">map</a>, then throw a <code class="idl"><a data-link-type="idl" href="https://heycam.github.io/webidl/#exceptiondef-typeerror" id="ref-for-exceptiondef-typeerror①">TypeError</a></code> indicating that the "<code>imports</code>" top-level key must be a JSON object.</p>
       <li data-md>
        <p>Set <var>sortedAndNormalizedImports</var> to the result of <a data-link-type="dfn" href="#sort-and-normalize-a-specifier-map" id="ref-for-sort-and-normalize-a-specifier-map">sorting and normalizing a specifier map</a> given <var>parsed</var>["<code>imports</code>"] and <var>baseURL</var>.</p>
      </ol>
     <li data-md>
      <p>Let <var>sortedAndNormalizedScopes</var> be an empty <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map⑤">map</a>.</p>
     <li data-md>
      <p>If <var>parsed</var>["<code>scopes</code>"] <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-exists" id="ref-for-map-exists①">exists</a>, then:</p>
      <ol>
       <li data-md>
        <p>If <var>parsed</var>["<code>scopes</code>"] is not a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map⑥">map</a>, then throw a <code class="idl"><a data-link-type="idl" href="https://heycam.github.io/webidl/#exceptiondef-typeerror" id="ref-for-exceptiondef-typeerror②">TypeError</a></code> indicating that the "<code>scopes</code>" top-level key must be a JSON object.</p>
       <li data-md>
        <p>Set <var>sortedAndNormalizedScopes</var> to the result of <a data-link-type="dfn" href="#sort-and-normalize-scopes" id="ref-for-sort-and-normalize-scopes">sorting and normalizing scopes</a> given <var>parsed</var>["<code>scopes</code>"] and <var>baseURL</var>.</p>
      </ol>
     <li data-md>
      <p>If <var>parsed</var>’s <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-getting-the-keys" id="ref-for-map-getting-the-keys">keys</a> <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#list-contain" id="ref-for-list-contain">contains</a> any items besides "<code>imports</code>" or "<code>scopes</code>", <a data-link-type="dfn" href="https://console.spec.whatwg.org/#report-a-warning-to-the-console" id="ref-for-report-a-warning-to-the-console">report a warning to the console</a> that an invalid top-level key was present in the import map.</p>
      <p class="note" role="note">This can help detect typos. It is not an error, because that would prevent any future extensions from being added backward-compatibly.</p>
     <li data-md>
      <p>Return the <a data-link-type="dfn" href="#import-map" id="ref-for-import-map⑥">import map</a> whose <a data-link-type="dfn" href="#import-map-imports" id="ref-for-import-map-imports①">imports</a> are <var>sortedAndNormalizedImports</var> and whose <a data-link-type="dfn" href="#import-map-scopes" id="ref-for-import-map-scopes①">scopes</a> scopes are <var>sortedAndNormalizedScopes</var>.</p>
    </ol>
   </div>
   <div class="algorithm" data-algorithm="create an import map parse result">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-noexport id="create-an-import-map-parse-result">create an import map parse result</dfn>, given a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string②">string</a> <var>input</var>, a <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url③">URL</a> <var>baseURL</var>, and an <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#environment-settings-object" id="ref-for-environment-settings-object②">environment settings object</a> <var>settings object</var>: 
    <ol>
     <li data-md>
      <p>Let <var>import map</var> be the result of <a data-link-type="dfn" href="#parse-an-import-map-string" id="ref-for-parse-an-import-map-string">parse an import map string</a> given <var>input</var> and <var>baseURL</var>. If this throws an exception, let <var>error to rethrow</var> be the exception. Otherwise, let <var>error to rethrow</var> be null.</p>
     <li data-md>
      <p>Return an <a data-link-type="dfn" href="#import-map-parse-result" id="ref-for-import-map-parse-result④">import map parse result</a> with <a data-link-type="dfn" href="#import-map-parse-result-settings-object" id="ref-for-import-map-parse-result-settings-object①">settings object</a> is <var>settings object</var>, <a data-link-type="dfn" href="#import-map-parse-result-import-map" id="ref-for-import-map-parse-result-import-map①">import map</a> is <var>import map</var>, and <a data-link-type="dfn" href="#import-map-parse-result-error-to-rethrow" id="ref-for-import-map-parse-result-error-to-rethrow②">error to rethrow</a> is <var>error to rethrow</var>.</p>
    </ol>
   </div>
   <div class="example" id="parsing-example">
    <a class="self-link" href="#parsing-example"></a> The <a data-link-type="dfn" href="#import-map" id="ref-for-import-map⑦">import map</a> is a highly normalized structure. For example, given a base URL of <code>&lt;https://example.com/base/page.html></code>, the input 
<pre class="highlight"><c- p>{</c->
  <c- f>"imports"</c-><c- p>:</c-> <c- p>{</c->
    <c- f>"/app/helper"</c-><c- p>:</c-> <c- u>"node_modules/helper/index.mjs"</c-><c- p>,</c->
    <c- f>"lodash"</c-><c- p>:</c-> <c- u>"/node_modules/lodash-es/lodash.js"</c->
  <c- p>}</c->
<c- p>}</c->
</pre>
    <p>will generate an <a data-link-type="dfn" href="#import-map" id="ref-for-import-map⑧">import map</a> with <a data-link-type="dfn" href="#import-map-imports" id="ref-for-import-map-imports②">imports</a> of</p>
<pre>«[
  "https://example.com/app/helper" → &lt;https://example.com/base/node_modules/helper/index.mjs>
  "lodash" → &lt;https://example.com/node_modules/lodash-es/lodash.js>
]»
</pre>
    <p>and (despite nothing being present in the input) an empty <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map⑦">map</a> for its <a data-link-type="dfn" href="#import-map-scopes" id="ref-for-import-map-scopes②">scopes</a>.</p>
   </div>
   <div class="algorithm" data-algorithm="sort and normalize a specifier map">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-lt="sort and normalize a specifier map|sorting and normalizing a specifier map" data-noexport id="sort-and-normalize-a-specifier-map">sort and normalize a specifier map</dfn>, given a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map⑧">map</a> <var>originalMap</var> and a <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url④">URL</a> <var>baseURL</var>: 
    <ol>
     <li data-md>
      <p>Let <var>normalized</var> be an empty <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map⑨">map</a>.</p>
     <li data-md>
      <p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-iterate" id="ref-for-map-iterate">For each</a> <var>specifierKey</var> → <var>value</var> of <var>originalMap</var>,</p>
      <ol>
       <li data-md>
        <p>Let <var>normalizedSpecifierKey</var> be the result of <a data-link-type="dfn" href="#normalize-a-specifier-key" id="ref-for-normalize-a-specifier-key">normalizing a specifier key</a> given <var>specifierKey</var> and <var>baseURL</var>.</p>
       <li data-md>
        <p>If <var>normalizedSpecifierKey</var> is null, then <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#iteration-continue" id="ref-for-iteration-continue">continue</a>.</p>
       <li data-md>
        <p>If <var>value</var> is not a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string③">string</a>, then:</p>
        <ol>
         <li data-md>
          <p><a data-link-type="dfn" href="https://console.spec.whatwg.org/#report-a-warning-to-the-console" id="ref-for-report-a-warning-to-the-console①">Report a warning to the console</a> that addresses must be strings.</p>
         <li data-md>
          <p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#iteration-continue" id="ref-for-iteration-continue①">Continue</a>.</p>
        </ol>
       <li data-md>
        <p>Let <var>addressURL</var> be the result of <a data-link-type="dfn" href="#parse-a-url-like-import-specifier" id="ref-for-parse-a-url-like-import-specifier">parsing a URL-like import specifier</a> given <var>value</var> and <var>baseURL</var>.</p>
       <li data-md>
        <p>If <var>addressURL</var> is null, then:</p>
        <ol>
         <li data-md>
          <p><a data-link-type="dfn" href="https://console.spec.whatwg.org/#report-a-warning-to-the-console" id="ref-for-report-a-warning-to-the-console②">Report a warning to the console</a> that the address was invalid.</p>
         <li data-md>
          <p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#iteration-continue" id="ref-for-iteration-continue②">Continue</a>.</p>
        </ol>
       <li data-md>
        <p>If <var>specifierKey</var> ends with U+002F (/), and the <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-serializer" id="ref-for-concept-url-serializer">serialization</a> of <var>addressURL</var> does not end with U+002F (/), then:</p>
        <ol>
         <li data-md>
          <p><a data-link-type="dfn" href="https://console.spec.whatwg.org/#report-a-warning-to-the-console" id="ref-for-report-a-warning-to-the-console③">Report a warning to the console</a> that an invalid address was given for the specifier key <var>specifierKey</var>; since <var>specifierKey</var> ended in a slash, so must the address.</p>
         <li data-md>
          <p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#iteration-continue" id="ref-for-iteration-continue③">Continue</a>.</p>
        </ol>
       <li data-md>
        <p>Set <var>normalized</var>[<var>specifierKey</var>] to <var>addressURL</var>.</p>
      </ol>
     <li data-md>
      <p>Return the result of <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-sort-in-ascending-order" id="ref-for-map-sort-in-ascending-order">sorting</a> <var>normalized</var>, with an entry <var>a</var> being less than an entry <var>b</var> if <var>b</var>’s <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-key" id="ref-for-map-key">key</a> is <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#code-unit-less-than" id="ref-for-code-unit-less-than">code unit less than</a> <var>a</var>’s <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-key" id="ref-for-map-key①">key</a>.</p>
    </ol>
   </div>
   <div class="algorithm" data-algorithm="sort and normalize scopes">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-lt="sort and normalize scopes|sorting and normalizing scopes" data-noexport id="sort-and-normalize-scopes">sort and normalize scopes</dfn>, given a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map①⓪">map</a> <var>originalMap</var> and a <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url⑤">URL</a> <var>baseURL</var>: 
    <ol>
     <li data-md>
      <p>Let <var>normalized</var> be an empty <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map①①">map</a>.</p>
     <li data-md>
      <p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-iterate" id="ref-for-map-iterate①">For each</a> <var>scopePrefix</var> → <var>potentialSpecifierMap</var> of <var>originalMap</var>,</p>
      <ol>
       <li data-md>
        <p>If <var>potentialSpecifierMap</var> is not a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#ordered-map" id="ref-for-ordered-map①②">map</a>, then throw a <code class="idl"><a data-link-type="idl" href="https://heycam.github.io/webidl/#exceptiondef-typeerror" id="ref-for-exceptiondef-typeerror③">TypeError</a></code> indicating that the value of the scope with prefix <var>scopePrefix</var> must be a JSON object.</p>
       <li data-md>
        <p>Let <var>scopePrefixURL</var> be the result of <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-parser" id="ref-for-concept-url-parser">parsing</a> <var>scopePrefix</var> with <var>baseURL</var> as the base URL.</p>
       <li data-md>
        <p>If <var>scopePrefixURL</var> is failure, then:</p>
        <ol>
         <li data-md>
          <p><a data-link-type="dfn" href="https://console.spec.whatwg.org/#report-a-warning-to-the-console" id="ref-for-report-a-warning-to-the-console④">Report a warning to the console</a> that the scope prefix URL was not parseable.</p>
         <li data-md>
          <p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#iteration-continue" id="ref-for-iteration-continue④">Continue</a>.</p>
        </ol>
       <li data-md>
        <p>Let <var>normalizedScopePrefix</var> be the <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-serializer" id="ref-for-concept-url-serializer①">serialization</a> of <var>scopePrefixURL</var>.</p>
       <li data-md>
        <p>Set <var>normalized</var>[<var>normalizedScopePrefix</var>] to the result of <a data-link-type="dfn" href="#sort-and-normalize-a-specifier-map" id="ref-for-sort-and-normalize-a-specifier-map①">sorting and normalizing a specifier map</a> given <var>potentialSpecifierMap</var> and <var>baseURL</var>.</p>
      </ol>
     <li data-md>
      <p>Return the result of <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-sort-in-ascending-order" id="ref-for-map-sort-in-ascending-order①">sorting</a> <var>normalized</var>, with an entry <var>a</var> being less than an entry <var>b</var> if <var>b</var>’s <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-key" id="ref-for-map-key②">key</a> is <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#code-unit-less-than" id="ref-for-code-unit-less-than①">code unit less than</a> <var>a</var>’s <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-key" id="ref-for-map-key③">key</a>.</p>
    </ol>
   </div>
   <p class="note" role="note">We sort keys/scopes in reverse order, to put <code>"foo/bar/"</code> before <code>"foo/"</code> so that <code>"foo/bar/"</code> has a higher priority than <code>"foo/"</code>.</p>
   <div class="algorithm" data-algorithm="normalize a specifier key">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-lt="normalize a specifier key|normalizing a specifier key" data-noexport id="normalize-a-specifier-key">normalize a specifier key</dfn>, given a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string④">string</a> <var>specifierKey</var> and a <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url⑥">URL</a> <var>baseURL</var>: 
    <ol>
     <li data-md>
      <p>If <var>specifierKey</var> is the empty string, then:</p>
      <ol>
       <li data-md>
        <p><a data-link-type="dfn" href="https://console.spec.whatwg.org/#report-a-warning-to-the-console" id="ref-for-report-a-warning-to-the-console⑤">Report a warning to the console</a> that specifier keys cannot be the empty string.</p>
       <li data-md>
        <p>Return null.</p>
      </ol>
     <li data-md>
      <p>Let <var>url</var> be the result of <a data-link-type="dfn" href="#parse-a-url-like-import-specifier" id="ref-for-parse-a-url-like-import-specifier①">parsing a URL-like import specifier</a>, given <var>specifierKey</var> and <var>baseURL</var>.</p>
     <li data-md>
      <p>If <var>url</var> is not null, then return the <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-serializer" id="ref-for-concept-url-serializer②">serialization</a> of <var>url</var>.</p>
     <li data-md>
      <p>Return <var>specifierKey</var>.</p>
    </ol>
   </div>
   <div class="algorithm" data-algorithm="parse a URL-like import specifier">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-lt="parse a URL-like import specifier|parsing a URL-like import specifier" data-noexport id="parse-a-url-like-import-specifier">parse a URL-like import specifier</dfn>, given a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string⑤">string</a> <var>specifier</var> and a <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url⑦">URL</a> <var>baseURL</var>: 
    <ol>
     <li data-md>
      <p>If <var>specifier</var> <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#code-unit-prefix" id="ref-for-code-unit-prefix">starts with</a> "<code>/</code>", "<code>./</code>", or "<code>../</code>", then:</p>
      <ol>
       <li data-md>
        <p>Let <var>url</var> be the result of <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-parser" id="ref-for-concept-url-parser①">parsing</a> <var>specifier</var> with <var>baseURL</var> as the base URL.</p>
       <li data-md>
        <p>If <var>url</var> is failure, then return null.</p>
        <p class="example" id="example-bad-urllike-import-specifier"><a class="self-link" href="#example-bad-urllike-import-specifier"></a>One way this could happen is if <var>specifier</var> is "<code>../foo</code>" and <var>baseURL</var> is a <code>data:</code> URL.</p>
       <li data-md>
        <p>Return <var>url</var>.</p>
      </ol>
     <li data-md>
      <p>Let <var>url</var> be the result of <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-parser" id="ref-for-concept-url-parser②">parsing</a> <var>specifier</var> (with no base URL).</p>
     <li data-md>
      <p>If <var>url</var> is failure, then return null.</p>
     <li data-md>
      <p>Return <var>url</var>.</p>
    </ol>
   </div>
   <h2 class="heading settled" data-level="4" id="resolving"><span class="secno">4. </span><span class="content">Resolving module specifiers</span><a class="self-link" href="#resolving"></a></h2>
   <h3 class="heading settled" data-level="4.1" id="new-resolve-algorithm"><span class="secno">4.1. </span><span class="content">New "resolve a module specifier"</span><a class="self-link" href="#new-resolve-algorithm"></a></h3>
   <div class="algorithm" data-algorithm="resolve a module specifier">
     HTML already has a <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#resolve-a-module-specifier" id="ref-for-resolve-a-module-specifier②">resolve a module specifier</a> algorithm. We replace it with the following <dfn class="dfn-paneled" data-dfn-type="dfn" data-export id="resolve-a-module-specifier">resolve a module specifier</dfn> algorithm, given a <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script" id="ref-for-concept-script④">script</a> <var>referringScript</var> and a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#javascript-string" id="ref-for-javascript-string">JavaScript string</a> <var>specifier</var>: 
    <ol>
     <li data-md>
      <p>Let <var>settingsObject</var> be the <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#current-settings-object" id="ref-for-current-settings-object">current settings object</a>.</p>
     <li data-md>
      <p>Let <var>baseURL</var> be <var>settingsObject</var>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#api-base-url" id="ref-for-api-base-url">API base URL</a>.</p>
     <li data-md>
      <p>If <var>referringScript</var> is not null, then:</p>
      <ol>
       <li data-md>
        <p>Set <var>settingsObject</var> to <var>referringScript</var>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#settings-object" id="ref-for-settings-object">settings object</a>.</p>
       <li data-md>
        <p>Set <var>baseURL</var> to <var>referringScript</var>’s <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script-base-url" id="ref-for-concept-script-base-url">base URL</a>.</p>
      </ol>
     <li data-md>
      <p>Let <var>importMap</var> be <var>settingsObject</var>’s <a data-link-type="dfn" href="#environment-settings-object-import-map" id="ref-for-environment-settings-object-import-map②">import map</a>.</p>
     <li data-md>
      <p>Let <var>baseURLString</var> be <var>baseURL</var>, <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-serializer" id="ref-for-concept-url-serializer③">serialized</a>.</p>
     <li data-md>
      <p>Let <var>asURL</var> be the result of <a data-link-type="dfn" href="#parse-a-url-like-import-specifier" id="ref-for-parse-a-url-like-import-specifier②">parsing a URL-like import specifier</a> given <var>specifier</var> and <var>baseURL</var>.</p>
     <li data-md>
      <p>Let <var>normalizedSpecifier</var> be the <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-serializer" id="ref-for-concept-url-serializer④">serialization</a> of <var>asURL</var>, if <var>asURL</var> is non-null; otherwise, <var>specifier</var>.</p>
     <li data-md>
      <p><a data-link-type="dfn" href="https://infra.spec.whatwg.org/#map-iterate" id="ref-for-map-iterate②">For each</a> <var>scopePrefix</var> → <var>scopeImports</var> of <var>importMap</var>’s <a data-link-type="dfn" href="#import-map-scopes" id="ref-for-import-map-scopes③">scopes</a>,</p>
      <ol>
       <li data-md>
        <p>If <var>scopePrefix</var> is <var>baseURLString</var>, or if <var>scopePrefix</var> ends with U+002F (/) and <var>baseURLString</var> <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#code-unit-prefix" id="ref-for-code-unit-prefix①">starts with</a> <var>scopePrefix</var>, then:</p>
        <ol>
         <li data-md>
          <p>Let <var>scopeImportsMatch</var> be the result of <a data-link-type="dfn" href="#resolve-an-imports-match" id="ref-for-resolve-an-imports-match">resolving an imports match</a> given <var>normalizedSpecifier</var> and <var>scopeImports</var>.</p>
         <li data-md>
          <p>If <var>scopeImportsMatch</var> is not null, then return <var>scopeImportsMatch</var>.</p>
        </ol>
      </ol>
     <li data-md>
      <p>Let <var>topLevelImportsMatch</var> be the result of <a data-link-type="dfn" href="#resolve-an-imports-match" id="ref-for-resolve-an-imports-match①">resolving an imports match</a> given <var>normalizedSpecifier</var> and <var>importMap</var>’s <a data-link-type="dfn" href="#import-map-imports" id="ref-for-import-map-imports③">imports</a>.</p>
     <li data-md>
      <p>If <var>topLevelImportsMatch</var> is not null, then return <var>topLevelImportsMatch</var>.</p>
     <li data-md>
      <p class="note" role="note">At this point, the specifier was able to be turned in to a URL, but it wasn’t remapped to anything by <var>importMap</var>.</p>
       If <var>asURL</var> is not null, then return <var>asURL</var>. 
     <li data-md>
      <p>Throw a <code class="idl"><a data-link-type="idl" href="https://heycam.github.io/webidl/#exceptiondef-typeerror" id="ref-for-exceptiondef-typeerror④">TypeError</a></code> indicating that <var>specifier</var> was a bare specifier, but was not remapped to anything by <var>importMap</var>.</p>
    </ol>
   </div>
   <div class="algorithm" data-algorithm="resolve an imports match">
     To <dfn class="dfn-paneled" data-dfn-type="dfn" data-lt="resolve an imports match|resolving an imports match" data-noexport id="resolve-an-imports-match">resolve an imports match</dfn>, given a <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#string" id="ref-for-string⑥">string</a> <var>normalizedSpecifier</var> and a <a data-link-type="dfn" href="#specifier-map" id="ref-for-specifier-map②">specifier map</a> <var>specifierMap</var>: 
    <ol>
     <li data-md>
      <p>For each <var>specifierKey</var> → <var>address</var> of <var>specifierMap</var>,</p>
      <ol>
       <li data-md>
        <p>If <var>specifierKey</var> is <var>normalizedSpecifier</var>, then return <var>address</var>.</p>
       <li data-md>
        <p>If <var>specifierKey</var> ends with U+002F (/) and <var>normalizedSpecifier</var> <a data-link-type="dfn" href="https://infra.spec.whatwg.org/#code-unit-prefix" id="ref-for-code-unit-prefix②">starts with</a> <var>specifierKey</var>, then:</p>
        <ol>
         <li data-md>
          <p>Let <var>afterPrefix</var> be the portion of <var>normalizedSpecifier</var> after the initial <var>specifierKey</var> prefix.</p>
         <li data-md>
          <p class="assertion">Assert: <var>afterPrefix</var> ends with "<code>/</code>", as enforced during <a data-link-type="dfn" href="#parse-an-import-map-string" id="ref-for-parse-an-import-map-string①">parsing</a>.</p>
         <li data-md>
          <p>Let <var>url</var> be the result of <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url-parser" id="ref-for-concept-url-parser③">parsing</a> <var>afterPrefix</var> relative to the base URL <var>address</var>.</p>
         <li data-md>
          <p>If <var>url</var> is failure, then return null.</p>
         <li data-md>
          <p>Return <var>url</var>.</p>
        </ol>
      </ol>
     <li data-md>
      <p>Return null.</p>
    </ol>
   </div>
   <h3 class="heading settled" data-level="4.2" id="resolving-updates"><span class="secno">4.2. </span><span class="content">Updates to other algorithms</span><a class="self-link" href="#resolving-updates"></a></h3>
   <p>All call sites of HTML’s existing <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#resolve-a-module-specifier" id="ref-for-resolve-a-module-specifier③">resolve a module specifier</a> will need to be updated to pass the appropriate <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script" id="ref-for-concept-script⑤">script</a>, not just its <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script-base-url" id="ref-for-concept-script-base-url①">base URL</a>. Some particular interesting cases:</p>
   <ul>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/infrastructure.html#js-hostresolveimportedmodule" id="ref-for-js-hostresolveimportedmodule">HostResolveImportedModule</a> and <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/infrastructure.html#js-hostimportmoduledynamically" id="ref-for-js-hostimportmoduledynamically">HostImportModuleDynamically</a> no longer need to compute the base URL themselves, as <a data-link-type="dfn" href="#resolve-a-module-specifier" id="ref-for-resolve-a-module-specifier④">resolve a module specifier</a> now handles that.</p>
    <li data-md>
     <p><a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-an-import()-module-script-graph" id="ref-for-fetch-an-import()-module-script-graph①">Fetch an import() module script graph</a> will also need to take a <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script" id="ref-for-concept-script⑥">script</a> instead of a base URL.</p>
   </ul>
   <p>Call sites will also need to be updated to account for <a data-link-type="dfn" href="#resolve-a-module-specifier" id="ref-for-resolve-a-module-specifier⑤">resolve a module specifier</a> now throwing exceptions, instead of returning failure. (Previously most call sites just turned failures into <code class="idl"><a data-link-type="idl" href="https://heycam.github.io/webidl/#exceptiondef-typeerror" id="ref-for-exceptiondef-typeerror⑤">TypeError</a></code>s manually, so this is straightforward.)</p>
   <h2 class="heading settled" data-level="5" id="security-and-privacy"><span class="secno">5. </span><span class="content">Security and Privacy</span><a class="self-link" href="#security-and-privacy"></a></h2>
   <h3 class="heading settled" data-level="5.1" id="threat-models"><span class="secno">5.1. </span><span class="content">Threat models</span><a class="self-link" href="#threat-models"></a></h3>
   <h4 class="heading settled" data-level="5.1.1" id="comparison-with-first-party-scripts"><span class="secno">5.1.1. </span><span class="content">Comparison with first-party scripts</span><a class="self-link" href="#comparison-with-first-party-scripts"></a></h4>
   <p>Import maps are explicitly designed to be installed by page authors, i.e. those who have the ability to run first-party scripts. (See the explainer’s <a href="https://github.com/WICG/import-maps/blob/master/README.md#scope">"Scope" section</a>.)</p>
   <p>Although it may seem that the ability to change how resources are imported from JavaScript and the capability of rewriting rules are powerful, there is no extra power really granted here, compared with first-party scripts. That is, they only change things which the page author could change already, by manually editing their code to use different URLs.</p>
   <p>We do still need to apply the traditional protections against first-party malicious actors, for example:</p>
   <ul>
    <li data-md>
     <p>CSP to protect against injection vulnerabilities. (See <a href="https://github.com/WICG/import-maps/issues/105">#105</a> for further discussion.)</p>
    <li data-md>
     <p>CORS and strict MIME type checking (with a new MIME type, "<code>application/importmap+json</code>") for external import maps.</p>
   </ul>
   <p>But there is no fundamentally new capability introduced here, that needs new consideration.</p>
   <h4 class="heading settled" data-level="5.1.2" id="comparison-with-service-workers"><span class="secno">5.1.2. </span><span class="content">Comparison with Service Workers</span><a class="self-link" href="#comparison-with-service-workers"></a></h4>
   <p>On one hand, the ability of import maps to change how resources are imported looks similar to the ability of Service Workers to intercept and rewrite fetch requests.</p>
   <p>On the other hand, import maps have a much more restricted scope than Service Workers. Import maps are not persistent, and an import map only affects the document that installs the import map via <code>&lt;script type="importmap"></code>.</p>
   <p>Therefore, the security restrictions applied to Service Workers (beyond those applied to first-party scripts), e.g. the same-origin/secure contexts requirements, are not applied to import maps.</p>
   <h4 class="heading settled" data-level="5.1.3" id="complexity"><span class="secno">5.1.3. </span><span class="content">Time/memory complexity</span><a class="self-link" href="#complexity"></a></h4>
   <p>To avoid denial of service attacks, explosive memory usage, and the like, import maps are designed to have reasonably bounded time and memory complexity in the worst cases, and to not be Turing complete.</p>
   <h3 class="heading settled" data-level="5.2" id="note-on-import-specifiers"><span class="secno">5.2. </span><span class="content">A note on import specifiers</span><a class="self-link" href="#note-on-import-specifiers"></a></h3>
   <p>The import specifiers that appear in <code>import</code> statements and <code>import()</code> expressions are not <a data-link-type="dfn" href="https://url.spec.whatwg.org/#concept-url" id="ref-for-concept-url⑧">URLs</a>, and should not be thought of as such.</p>
   <p>To date, there has been a <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#resolve-a-module-specifier" id="ref-for-resolve-a-module-specifier⑥">default mechanism</a> for translating those strings into URLs. And indeed, some of the strings, such as <code>"https://example.com/foo.mjs"</code>, or <code>"./bar.mjs"</code>, might look URL-like; for those, the default translation does what you would expect.</p>
   <p>But overall, one should not think of <code>import(x)</code> as corresponding to <code>fetch(x)</code>. Instead, the correspondence is to <code>fetch(translate(x))</code>, where the translation algorithm produces the actual URL to be fetched. In this framing, the way to think about import maps is as providing a mechanism for overriding the default mechanism, i.e. customizing the <code>translate()</code> function.</p>
   <p>This brings some clarity to some common security questions. For example: given an import map which maps the specifier <code>"https://1.example.com/foo.mjs"</code> to the URL <code>&lt;https://2.example.com/bar.mjs></code>, should we apply CSP checks to <code>&lt;https://1.example.com/foo.mjs></code> or to <code>&lt;https://2.example.com/bar.mjs></code>? With this framing we can see that we should apply the checks to the post-translation URL <code>&lt;https://2.example.com/bar.mjs></code> which is actually fetched, and not to the pre-translation <code>"https://1.example.com/foo.mjs"</code> module specifier.</p>
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  <h2 class="no-num no-ref heading settled" id="index"><span class="content">Index</span><a class="self-link" href="#index"></a></h2>
  <h3 class="no-num no-ref heading settled" id="index-defined-here"><span class="content">Terms defined by this specification</span><a class="self-link" href="#index-defined-here"></a></h3>
  <ul class="index">
   <li><a href="#document-acquiring-import-maps">acquiring import maps</a><span>, in §2.1</span>
   <li><a href="#create-an-import-map-parse-result">create an import map parse result</a><span>, in §3</span>
   <li><a href="#empty-import-map">empty import map</a><span>, in §1</span>
   <li><a href="#import-map-parse-result-error-to-rethrow">error to rethrow</a><span>, in §2.2</span>
   <li><a href="#fetch-an-import-map">fetch an import map</a><span>, in §2.3</span>
   <li>
    import map
    <ul>
     <li><a href="#import-map">definition of</a><span>, in §1</span>
     <li><a href="#document-import-map">dfn for Document</a><span>, in §2.1</span>
     <li><a href="#workerglobalscope-import-map">dfn for WorkerGlobalScope</a><span>, in §2.1</span>
     <li><a href="#environment-settings-object-import-map">dfn for environment settings object</a><span>, in §2.1</span>
     <li><a href="#import-map-parse-result-import-map">dfn for import map parse result</a><span>, in §2.2</span>
    </ul>
   <li><a href="#import-map-parse-result">import map parse result</a><span>, in §2.2</span>
   <li><a href="#import-map-imports">imports</a><span>, in §1</span>
   <li><a href="#normalize-a-specifier-key">normalize a specifier key</a><span>, in §3</span>
   <li><a href="#normalize-a-specifier-key">normalizing a specifier key</a><span>, in §3</span>
   <li><a href="#parse-an-import-map-string">parse an import map string</a><span>, in §3</span>
   <li><a href="#parse-a-url-like-import-specifier">parse a URL-like import specifier</a><span>, in §3</span>
   <li><a href="#parse-an-import-map-string">parsing an import map string</a><span>, in §3</span>
   <li><a href="#parse-a-url-like-import-specifier">parsing a URL-like import specifier</a><span>, in §3</span>
   <li><a href="#document-pending-import-map-script">pending import map script</a><span>, in §2.1</span>
   <li><a href="#register-an-import-map">register an import map</a><span>, in §2.5</span>
   <li><a href="#resolve-a-module-specifier">resolve a module specifier</a><span>, in §4.1</span>
   <li><a href="#resolve-an-imports-match">resolve an imports match</a><span>, in §4.1</span>
   <li><a href="#resolve-an-imports-match">resolving an imports match</a><span>, in §4.1</span>
   <li><a href="#import-map-scopes">scopes</a><span>, in §1</span>
   <li><a href="#import-map-parse-result-settings-object">settings object</a><span>, in §2.2</span>
   <li><a href="#sort-and-normalize-a-specifier-map">sort and normalize a specifier map</a><span>, in §3</span>
   <li><a href="#sort-and-normalize-scopes">sort and normalize scopes</a><span>, in §3</span>
   <li><a href="#sort-and-normalize-a-specifier-map">sorting and normalizing a specifier map</a><span>, in §3</span>
   <li><a href="#sort-and-normalize-scopes">sorting and normalizing scopes</a><span>, in §3</span>
   <li><a href="#specifier-map">specifier map</a><span>, in §1</span>
   <li><a href="#the-scripts-result">the script’s result</a><span>, in §2.2</span>
   <li><a href="#wait-for-import-maps">wait for import maps</a><span>, in §2.4</span>
  </ul>
  <aside class="dfn-panel" data-for="term-for-report-a-warning-to-the-console">
   <a href="https://console.spec.whatwg.org/#report-a-warning-to-the-console">https://console.spec.whatwg.org/#report-a-warning-to-the-console</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-report-a-warning-to-the-console">3. Parsing import maps</a> <a href="#ref-for-report-a-warning-to-the-console①">(2)</a> <a href="#ref-for-report-a-warning-to-the-console②">(3)</a> <a href="#ref-for-report-a-warning-to-the-console③">(4)</a> <a href="#ref-for-report-a-warning-to-the-console④">(5)</a> <a href="#ref-for-report-a-warning-to-the-console⑤">(6)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-document">
   <a href="https://dom.spec.whatwg.org/#document">https://dom.spec.whatwg.org/#document</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-document">2.1. New members of environment settings objects</a> <a href="#ref-for-document①">(2)</a> <a href="#ref-for-document②">(3)</a>
    <li><a href="#ref-for-document③">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-event-fire">
   <a href="https://dom.spec.whatwg.org/#concept-event-fire">https://dom.spec.whatwg.org/#concept-event-fire</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-event-fire①">2.5. Registering an import map</a> <a href="#ref-for-concept-event-fire②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-node-document">
   <a href="https://dom.spec.whatwg.org/#concept-node-document">https://dom.spec.whatwg.org/#concept-node-document</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-node-document">2.3. Prepare a script</a> <a href="#ref-for-concept-node-document①">(2)</a> <a href="#ref-for-concept-node-document②">(3)</a>
    <li><a href="#ref-for-concept-node-document③">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-utf-8-decode">
   <a href="https://encoding.spec.whatwg.org/#utf-8-decode">https://encoding.spec.whatwg.org/#utf-8-decode</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-utf-8-decode">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-response-body">
   <a href="https://fetch.spec.whatwg.org/#concept-response-body">https://fetch.spec.whatwg.org/#concept-response-body</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-response-body">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-request-client">
   <a href="https://fetch.spec.whatwg.org/#concept-request-client">https://fetch.spec.whatwg.org/#concept-request-client</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-request-client">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-request-destination">
   <a href="https://fetch.spec.whatwg.org/#concept-request-destination">https://fetch.spec.whatwg.org/#concept-request-destination</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-request-destination">2.3. Prepare a script</a> <a href="#ref-for-concept-request-destination①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-header-extract-mime-type">
   <a href="https://fetch.spec.whatwg.org/#concept-header-extract-mime-type">https://fetch.spec.whatwg.org/#concept-header-extract-mime-type</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-header-extract-mime-type">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-fetch">
   <a href="https://fetch.spec.whatwg.org/#concept-fetch">https://fetch.spec.whatwg.org/#concept-fetch</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-fetch">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-response-header-list">
   <a href="https://fetch.spec.whatwg.org/#concept-response-header-list">https://fetch.spec.whatwg.org/#concept-response-header-list</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-response-header-list">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-request-mode">
   <a href="https://fetch.spec.whatwg.org/#concept-request-mode">https://fetch.spec.whatwg.org/#concept-request-mode</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-request-mode">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-ok-status">
   <a href="https://fetch.spec.whatwg.org/#ok-status">https://fetch.spec.whatwg.org/#ok-status</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-ok-status">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-process-response">
   <a href="https://fetch.spec.whatwg.org/#process-response">https://fetch.spec.whatwg.org/#process-response</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-process-response">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-request-referrer">
   <a href="https://fetch.spec.whatwg.org/#concept-request-referrer">https://fetch.spec.whatwg.org/#concept-request-referrer</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-request-referrer">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-request">
   <a href="https://fetch.spec.whatwg.org/#concept-request">https://fetch.spec.whatwg.org/#concept-request</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-request">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-response">
   <a href="https://fetch.spec.whatwg.org/#concept-response">https://fetch.spec.whatwg.org/#concept-response</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-response">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-response-status">
   <a href="https://fetch.spec.whatwg.org/#concept-response-status">https://fetch.spec.whatwg.org/#concept-response-status</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-response-status">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-response-type">
   <a href="https://fetch.spec.whatwg.org/#concept-response-type">https://fetch.spec.whatwg.org/#concept-response-type</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-response-type">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-response-url">
   <a href="https://fetch.spec.whatwg.org/#concept-response-url">https://fetch.spec.whatwg.org/#concept-response-url</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-response-url">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-htmlscriptelement">
   <a href="https://html.spec.whatwg.org/multipage/scripting.html#htmlscriptelement">https://html.spec.whatwg.org/multipage/scripting.html#htmlscriptelement</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-htmlscriptelement">2.1. New members of environment settings objects</a>
    <li><a href="#ref-for-htmlscriptelement①">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-window">
   <a href="https://html.spec.whatwg.org/multipage/window-object.html#window">https://html.spec.whatwg.org/multipage/window-object.html#window</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-window">2.4. Wait for import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-workerglobalscope">
   <a href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope">https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-workerglobalscope">2.1. New members of environment settings objects</a> <a href="#ref-for-workerglobalscope①">(2)</a> <a href="#ref-for-workerglobalscope②">(3)</a>
    <li><a href="#ref-for-workerglobalscope③">2.4. Wait for import maps</a> <a href="#ref-for-workerglobalscope④">(2)</a> <a href="#ref-for-workerglobalscope⑤">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-api-base-url">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#api-base-url">https://html.spec.whatwg.org/multipage/webappapis.html#api-base-url</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-api-base-url">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-document-window">
   <a href="https://html.spec.whatwg.org/multipage/window-object.html#concept-document-window">https://html.spec.whatwg.org/multipage/window-object.html#concept-document-window</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-document-window">2.1. New members of environment settings objects</a>
    <li><a href="#ref-for-concept-document-window①">2.4. Wait for import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-script-base-url">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script-base-url">https://html.spec.whatwg.org/multipage/webappapis.html#concept-script-base-url</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-script-base-url">4.1. New "resolve a module specifier"</a>
    <li><a href="#ref-for-concept-script-base-url①">4.2. Updates to other algorithms</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-cors-same-origin">
   <a href="https://html.spec.whatwg.org/multipage/urls-and-fetching.html#cors-same-origin">https://html.spec.whatwg.org/multipage/urls-and-fetching.html#cors-same-origin</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-cors-same-origin">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-current-settings-object">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#current-settings-object">https://html.spec.whatwg.org/multipage/webappapis.html#current-settings-object</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-current-settings-object">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-environment-settings-object">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#environment-settings-object">https://html.spec.whatwg.org/multipage/webappapis.html#environment-settings-object</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-environment-settings-object">2.1. New members of environment settings objects</a>
    <li><a href="#ref-for-environment-settings-object①">2.2. Script type</a>
    <li><a href="#ref-for-environment-settings-object②">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-execute-the-script-block">
   <a href="https://html.spec.whatwg.org/multipage/scripting.html#execute-the-script-block">https://html.spec.whatwg.org/multipage/scripting.html#execute-the-script-block</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-execute-the-script-block">2.2. Script type</a> <a href="#ref-for-execute-the-script-block①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fetch-a-module-worker-script-tree">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-module-worker-script-tree">https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-module-worker-script-tree</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fetch-a-module-worker-script-tree">2.4. Wait for import maps</a> <a href="#ref-for-fetch-a-module-worker-script-tree①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fetch-a-modulepreload-module-script-graph">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-modulepreload-module-script-graph">https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-modulepreload-module-script-graph</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fetch-a-modulepreload-module-script-graph">2.4. Wait for import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fetch-a-single-module-script">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-single-module-script">https://html.spec.whatwg.org/multipage/webappapis.html#fetch-a-single-module-script</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fetch-a-single-module-script">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fetch-an-import()-module-script-graph">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-an-import()-module-script-graph">https://html.spec.whatwg.org/multipage/webappapis.html#fetch-an-import()-module-script-graph</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fetch-an-import()-module-script-graph">2.4. Wait for import maps</a>
    <li><a href="#ref-for-fetch-an-import()-module-script-graph①">4.2. Updates to other algorithms</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-fetch-an-inline-module-script-graph">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#fetch-an-inline-module-script-graph">https://html.spec.whatwg.org/multipage/webappapis.html#fetch-an-inline-module-script-graph</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fetch-an-inline-module-script-graph">2.4. Wait for import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-event-fire">
   <a href="https://html.spec.whatwg.org/multipage/infrastructure.html#concept-event-fire">https://html.spec.whatwg.org/multipage/infrastructure.html#concept-event-fire</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-event-fire">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-script-external">
   <a href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-external">https://html.spec.whatwg.org/multipage/scripting.html#concept-script-external</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-script-external">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-settings-object-global">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-settings-object-global">https://html.spec.whatwg.org/multipage/webappapis.html#concept-settings-object-global</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-settings-object-global">2.4. Wait for import maps</a> <a href="#ref-for-concept-settings-object-global①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-js-hostimportmoduledynamically">
   <a href="https://html.spec.whatwg.org/multipage/infrastructure.html#js-hostimportmoduledynamically">https://html.spec.whatwg.org/multipage/infrastructure.html#js-hostimportmoduledynamically</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-js-hostimportmoduledynamically">4.2. Updates to other algorithms</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-js-hostresolveimportedmodule">
   <a href="https://html.spec.whatwg.org/multipage/infrastructure.html#js-hostresolveimportedmodule">https://html.spec.whatwg.org/multipage/infrastructure.html#js-hostresolveimportedmodule</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-js-hostresolveimportedmodule">4.2. Updates to other algorithms</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-list-of-scripts-that-will-execute-in-order-as-soon-as-possible">
   <a href="https://html.spec.whatwg.org/multipage/scripting.html#list-of-scripts-that-will-execute-in-order-as-soon-as-possible">https://html.spec.whatwg.org/multipage/scripting.html#list-of-scripts-that-will-execute-in-order-as-soon-as-possible</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-list-of-scripts-that-will-execute-in-order-as-soon-as-possible">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-node-document">
   <a href="https://html.spec.whatwg.org/multipage/infrastructure.html#node-document">https://html.spec.whatwg.org/multipage/infrastructure.html#node-document</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-node-document">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-prepare-a-script">
   <a href="https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script">https://html.spec.whatwg.org/multipage/scripting.html#prepare-a-script</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-prepare-a-script">2.2. Script type</a> <a href="#ref-for-prepare-a-script①">(2)</a>
    <li><a href="#ref-for-prepare-a-script②">2.3. Prepare a script</a> <a href="#ref-for-prepare-a-script③">(2)</a> <a href="#ref-for-prepare-a-script④">(3)</a> <a href="#ref-for-prepare-a-script⑤">(4)</a> <a href="#ref-for-prepare-a-script⑥">(5)</a> <a href="#ref-for-prepare-a-script⑦">(6)</a> <a href="#ref-for-prepare-a-script⑧">(7)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-queue-a-task">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#queue-a-task">https://html.spec.whatwg.org/multipage/webappapis.html#queue-a-task</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-queue-a-task">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-relevant-settings-object">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#relevant-settings-object">https://html.spec.whatwg.org/multipage/webappapis.html#relevant-settings-object</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-relevant-settings-object">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-report-the-exception">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#report-the-exception">https://html.spec.whatwg.org/multipage/webappapis.html#report-the-exception</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-report-the-exception">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-resolve-a-module-specifier">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#resolve-a-module-specifier">https://html.spec.whatwg.org/multipage/webappapis.html#resolve-a-module-specifier</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-resolve-a-module-specifier②">4.1. New "resolve a module specifier"</a>
    <li><a href="#ref-for-resolve-a-module-specifier③">4.2. Updates to other algorithms</a>
    <li><a href="#ref-for-resolve-a-module-specifier⑥">5.2. A note on import specifiers</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-script">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script">https://html.spec.whatwg.org/multipage/webappapis.html#concept-script</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-script">2.2. Script type</a> <a href="#ref-for-concept-script①">(2)</a>
    <li><a href="#ref-for-concept-script②">2.5. Registering an import map</a> <a href="#ref-for-concept-script③">(2)</a>
    <li><a href="#ref-for-concept-script④">4.1. New "resolve a module specifier"</a>
    <li><a href="#ref-for-concept-script⑤">4.2. Updates to other algorithms</a> <a href="#ref-for-concept-script⑥">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-set-up-a-window-environment-settings-object">
   <a href="https://html.spec.whatwg.org/multipage/window-object.html#set-up-a-window-environment-settings-object">https://html.spec.whatwg.org/multipage/window-object.html#set-up-a-window-environment-settings-object</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-set-up-a-window-environment-settings-object">2.1. New members of environment settings objects</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-set-up-a-worker-environment-settings-object">
   <a href="https://html.spec.whatwg.org/multipage/workers.html#set-up-a-worker-environment-settings-object">https://html.spec.whatwg.org/multipage/workers.html#set-up-a-worker-environment-settings-object</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-set-up-a-worker-environment-settings-object">2.1. New members of environment settings objects</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-set-up-the-module-script-request">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#set-up-the-module-script-request">https://html.spec.whatwg.org/multipage/webappapis.html#set-up-the-module-script-request</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-set-up-the-module-script-request">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-settings-object">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#settings-object">https://html.spec.whatwg.org/multipage/webappapis.html#settings-object</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-settings-object">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-spin-the-event-loop">
   <a href="https://html.spec.whatwg.org/multipage/webappapis.html#spin-the-event-loop">https://html.spec.whatwg.org/multipage/webappapis.html#spin-the-event-loop</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-spin-the-event-loop">2.4. Wait for import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-the-script-is-ready">
   <a href="https://html.spec.whatwg.org/multipage/scripting.html#the-script-is-ready">https://html.spec.whatwg.org/multipage/scripting.html#the-script-is-ready</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-script-is-ready">2.3. Prepare a script</a> <a href="#ref-for-the-script-is-ready①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-script-script">
   <a href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-script">https://html.spec.whatwg.org/multipage/scripting.html#concept-script-script</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-script-script">2.2. Script type</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-script-type">
   <a href="https://html.spec.whatwg.org/multipage/scripting.html#concept-script-type">https://html.spec.whatwg.org/multipage/scripting.html#concept-script-type</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-script-type">2.2. Script type</a>
    <li><a href="#ref-for-concept-script-type①">2.3. Prepare a script</a> <a href="#ref-for-concept-script-type②">(2)</a> <a href="#ref-for-concept-script-type③">(3)</a>
    <li><a href="#ref-for-concept-script-type④">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-ascii-case-insensitive">
   <a href="https://infra.spec.whatwg.org/#ascii-case-insensitive">https://infra.spec.whatwg.org/#ascii-case-insensitive</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-ascii-case-insensitive">2.3. Prepare a script</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-code-unit-less-than">
   <a href="https://infra.spec.whatwg.org/#code-unit-less-than">https://infra.spec.whatwg.org/#code-unit-less-than</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-code-unit-less-than">3. Parsing import maps</a> <a href="#ref-for-code-unit-less-than①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-list-contain">
   <a href="https://infra.spec.whatwg.org/#list-contain">https://infra.spec.whatwg.org/#list-contain</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-list-contain">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-iteration-continue">
   <a href="https://infra.spec.whatwg.org/#iteration-continue">https://infra.spec.whatwg.org/#iteration-continue</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-iteration-continue">3. Parsing import maps</a> <a href="#ref-for-iteration-continue①">(2)</a> <a href="#ref-for-iteration-continue②">(3)</a> <a href="#ref-for-iteration-continue③">(4)</a> <a href="#ref-for-iteration-continue④">(5)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-map-exists">
   <a href="https://infra.spec.whatwg.org/#map-exists">https://infra.spec.whatwg.org/#map-exists</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-map-exists">3. Parsing import maps</a> <a href="#ref-for-map-exists①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-map-iterate">
   <a href="https://infra.spec.whatwg.org/#map-iterate">https://infra.spec.whatwg.org/#map-iterate</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-map-iterate">3. Parsing import maps</a> <a href="#ref-for-map-iterate①">(2)</a>
    <li><a href="#ref-for-map-iterate②">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-map-getting-the-keys">
   <a href="https://infra.spec.whatwg.org/#map-getting-the-keys">https://infra.spec.whatwg.org/#map-getting-the-keys</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-map-getting-the-keys">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-struct-item">
   <a href="https://infra.spec.whatwg.org/#struct-item">https://infra.spec.whatwg.org/#struct-item</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-struct-item">1. Definitions</a>
    <li><a href="#ref-for-struct-item①">2.2. Script type</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-javascript-string">
   <a href="https://infra.spec.whatwg.org/#javascript-string">https://infra.spec.whatwg.org/#javascript-string</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-javascript-string">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-map-key">
   <a href="https://infra.spec.whatwg.org/#map-key">https://infra.spec.whatwg.org/#map-key</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-map-key">3. Parsing import maps</a> <a href="#ref-for-map-key①">(2)</a> <a href="#ref-for-map-key②">(3)</a> <a href="#ref-for-map-key③">(4)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-ordered-map">
   <a href="https://infra.spec.whatwg.org/#ordered-map">https://infra.spec.whatwg.org/#ordered-map</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-ordered-map">1. Definitions</a> <a href="#ref-for-ordered-map①">(2)</a>
    <li><a href="#ref-for-ordered-map②">3. Parsing import maps</a> <a href="#ref-for-ordered-map③">(2)</a> <a href="#ref-for-ordered-map④">(3)</a> <a href="#ref-for-ordered-map⑤">(4)</a> <a href="#ref-for-ordered-map⑥">(5)</a> <a href="#ref-for-ordered-map⑦">(6)</a> <a href="#ref-for-ordered-map⑧">(7)</a> <a href="#ref-for-ordered-map⑨">(8)</a> <a href="#ref-for-ordered-map①⓪">(9)</a> <a href="#ref-for-ordered-map①①">(10)</a> <a href="#ref-for-ordered-map①②">(11)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-ordered-map">
   <a href="https://infra.spec.whatwg.org/#ordered-map">https://infra.spec.whatwg.org/#ordered-map</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-ordered-map">1. Definitions</a> <a href="#ref-for-ordered-map①">(2)</a>
    <li><a href="#ref-for-ordered-map②">3. Parsing import maps</a> <a href="#ref-for-ordered-map③">(2)</a> <a href="#ref-for-ordered-map④">(3)</a> <a href="#ref-for-ordered-map⑤">(4)</a> <a href="#ref-for-ordered-map⑥">(5)</a> <a href="#ref-for-ordered-map⑦">(6)</a> <a href="#ref-for-ordered-map⑧">(7)</a> <a href="#ref-for-ordered-map⑨">(8)</a> <a href="#ref-for-ordered-map①⓪">(9)</a> <a href="#ref-for-ordered-map①①">(10)</a> <a href="#ref-for-ordered-map①②">(11)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-parse-json-into-infra-values">
   <a href="https://infra.spec.whatwg.org/#parse-json-into-infra-values">https://infra.spec.whatwg.org/#parse-json-into-infra-values</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-parse-json-into-infra-values">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-map-sort-in-ascending-order">
   <a href="https://infra.spec.whatwg.org/#map-sort-in-ascending-order">https://infra.spec.whatwg.org/#map-sort-in-ascending-order</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-map-sort-in-ascending-order">3. Parsing import maps</a> <a href="#ref-for-map-sort-in-ascending-order①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-code-unit-prefix">
   <a href="https://infra.spec.whatwg.org/#code-unit-prefix">https://infra.spec.whatwg.org/#code-unit-prefix</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-code-unit-prefix">3. Parsing import maps</a>
    <li><a href="#ref-for-code-unit-prefix①">4.1. New "resolve a module specifier"</a> <a href="#ref-for-code-unit-prefix②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-string">
   <a href="https://infra.spec.whatwg.org/#string">https://infra.spec.whatwg.org/#string</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-string">1. Definitions</a>
    <li><a href="#ref-for-string①">3. Parsing import maps</a> <a href="#ref-for-string②">(2)</a> <a href="#ref-for-string③">(3)</a> <a href="#ref-for-string④">(4)</a> <a href="#ref-for-string⑤">(5)</a>
    <li><a href="#ref-for-string⑥">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-struct">
   <a href="https://infra.spec.whatwg.org/#struct">https://infra.spec.whatwg.org/#struct</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-struct">1. Definitions</a>
    <li><a href="#ref-for-struct①">2.2. Script type</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-url">
   <a href="https://url.spec.whatwg.org/#concept-url">https://url.spec.whatwg.org/#concept-url</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-url">1. Definitions</a> <a href="#ref-for-concept-url①">(2)</a>
    <li><a href="#ref-for-concept-url②">3. Parsing import maps</a> <a href="#ref-for-concept-url③">(2)</a> <a href="#ref-for-concept-url④">(3)</a> <a href="#ref-for-concept-url⑤">(4)</a> <a href="#ref-for-concept-url⑥">(5)</a> <a href="#ref-for-concept-url⑦">(6)</a>
    <li><a href="#ref-for-concept-url⑧">5.2. A note on import specifiers</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-url-parser">
   <a href="https://url.spec.whatwg.org/#concept-url-parser">https://url.spec.whatwg.org/#concept-url-parser</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-url-parser">3. Parsing import maps</a> <a href="#ref-for-concept-url-parser①">(2)</a> <a href="#ref-for-concept-url-parser②">(3)</a>
    <li><a href="#ref-for-concept-url-parser③">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-concept-url-serializer">
   <a href="https://url.spec.whatwg.org/#concept-url-serializer">https://url.spec.whatwg.org/#concept-url-serializer</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-concept-url-serializer">3. Parsing import maps</a> <a href="#ref-for-concept-url-serializer①">(2)</a> <a href="#ref-for-concept-url-serializer②">(3)</a>
    <li><a href="#ref-for-concept-url-serializer③">4.1. New "resolve a module specifier"</a> <a href="#ref-for-concept-url-serializer④">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="term-for-exceptiondef-typeerror">
   <a href="https://heycam.github.io/webidl/#exceptiondef-typeerror">https://heycam.github.io/webidl/#exceptiondef-typeerror</a><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-exceptiondef-typeerror">3. Parsing import maps</a> <a href="#ref-for-exceptiondef-typeerror①">(2)</a> <a href="#ref-for-exceptiondef-typeerror②">(3)</a> <a href="#ref-for-exceptiondef-typeerror③">(4)</a>
    <li><a href="#ref-for-exceptiondef-typeerror④">4.1. New "resolve a module specifier"</a>
    <li><a href="#ref-for-exceptiondef-typeerror⑤">4.2. Updates to other algorithms</a>
   </ul>
  </aside>
  <h3 class="no-num no-ref heading settled" id="index-defined-elsewhere"><span class="content">Terms defined by reference</span><a class="self-link" href="#index-defined-elsewhere"></a></h3>
  <ul class="index">
   <li>
    <a data-link-type="biblio">[CONSOLE]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-report-a-warning-to-the-console" style="color:initial">report a warning to the console</span>
    </ul>
   <li>
    <a data-link-type="biblio">[DOM]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-document" style="color:initial">Document</span>
     <li><span class="dfn-paneled" id="term-for-concept-event-fire" style="color:initial">fire an event</span>
     <li><span class="dfn-paneled" id="term-for-concept-node-document" style="color:initial">node document</span>
    </ul>
   <li>
    <a data-link-type="biblio">[ENCODING]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-utf-8-decode" style="color:initial">utf-8 decode</span>
    </ul>
   <li>
    <a data-link-type="biblio">[FETCH]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-concept-response-body" style="color:initial">body</span>
     <li><span class="dfn-paneled" id="term-for-concept-request-client" style="color:initial">client</span>
     <li><span class="dfn-paneled" id="term-for-concept-request-destination" style="color:initial">destination</span>
     <li><span class="dfn-paneled" id="term-for-concept-header-extract-mime-type" style="color:initial">extracting a mime type</span>
     <li><span class="dfn-paneled" id="term-for-concept-fetch" style="color:initial">fetch</span>
     <li><span class="dfn-paneled" id="term-for-concept-response-header-list" style="color:initial">header list</span>
     <li><span class="dfn-paneled" id="term-for-concept-request-mode" style="color:initial">mode</span>
     <li><span class="dfn-paneled" id="term-for-ok-status" style="color:initial">ok status</span>
     <li><span class="dfn-paneled" id="term-for-process-response" style="color:initial">process response</span>
     <li><span class="dfn-paneled" id="term-for-concept-request-referrer" style="color:initial">referrer</span>
     <li><span class="dfn-paneled" id="term-for-concept-request" style="color:initial">request</span>
     <li><span class="dfn-paneled" id="term-for-concept-response" style="color:initial">response</span>
     <li><span class="dfn-paneled" id="term-for-concept-response-status" style="color:initial">status</span>
     <li><span class="dfn-paneled" id="term-for-concept-response-type" style="color:initial">type</span>
     <li><span class="dfn-paneled" id="term-for-concept-response-url" style="color:initial">url <small>(for response)</small></span>
    </ul>
   <li>
    <a data-link-type="biblio">[HTML]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-htmlscriptelement" style="color:initial">HTMLScriptElement</span>
     <li><span class="dfn-paneled" id="term-for-window" style="color:initial">Window</span>
     <li><span class="dfn-paneled" id="term-for-workerglobalscope" style="color:initial">WorkerGlobalScope</span>
     <li><span class="dfn-paneled" id="term-for-api-base-url" style="color:initial">api base url</span>
     <li><span class="dfn-paneled" id="term-for-concept-document-window" style="color:initial">associated document</span>
     <li><span class="dfn-paneled" id="term-for-concept-script-base-url" style="color:initial">base url</span>
     <li><span class="dfn-paneled" id="term-for-cors-same-origin" style="color:initial">cors-same-origin</span>
     <li><span class="dfn-paneled" id="term-for-current-settings-object" style="color:initial">current settings object</span>
     <li><span class="dfn-paneled" id="term-for-environment-settings-object" style="color:initial">environment settings object</span>
     <li><span class="dfn-paneled" id="term-for-execute-the-script-block" style="color:initial">execute a script block</span>
     <li><span class="dfn-paneled" id="term-for-fetch-a-module-worker-script-tree" style="color:initial">fetch a module worker script graph</span>
     <li><span class="dfn-paneled" id="term-for-fetch-a-modulepreload-module-script-graph" style="color:initial">fetch a modulepreload module script graph</span>
     <li><span class="dfn-paneled" id="term-for-fetch-a-single-module-script" style="color:initial">fetch a single module script</span>
     <li><span class="dfn-paneled" id="term-for-fetch-an-import()-module-script-graph" style="color:initial">fetch an import() module script graph</span>
     <li><span class="dfn-paneled" id="term-for-fetch-an-inline-module-script-graph" style="color:initial">fetch an inline module script graph</span>
     <li><span class="dfn-paneled" id="term-for-concept-event-fire①" style="color:initial">fire an event</span>
     <li><span class="dfn-paneled" id="term-for-concept-script-external" style="color:initial">from an external file</span>
     <li><span class="dfn-paneled" id="term-for-concept-settings-object-global" style="color:initial">global object</span>
     <li><span class="dfn-paneled" id="term-for-js-hostimportmoduledynamically" style="color:initial">hostimportmoduledynamically</span>
     <li><span class="dfn-paneled" id="term-for-js-hostresolveimportedmodule" style="color:initial">hostresolveimportedmodule</span>
     <li><span class="dfn-paneled" id="term-for-list-of-scripts-that-will-execute-in-order-as-soon-as-possible" style="color:initial">list of scripts that will execute in order as soon as possible</span>
     <li><span class="dfn-paneled" id="term-for-node-document" style="color:initial">node document</span>
     <li><span class="dfn-paneled" id="term-for-prepare-a-script" style="color:initial">prepare a script</span>
     <li><span class="dfn-paneled" id="term-for-queue-a-task" style="color:initial">queue a task</span>
     <li><span class="dfn-paneled" id="term-for-relevant-settings-object" style="color:initial">relevant settings object</span>
     <li><span class="dfn-paneled" id="term-for-report-the-exception" style="color:initial">report the exception</span>
     <li><span class="dfn-paneled" id="term-for-resolve-a-module-specifier" style="color:initial">resolve a module specifier</span>
     <li><span class="dfn-paneled" id="term-for-concept-script" style="color:initial">script</span>
     <li><span class="dfn-paneled" id="term-for-set-up-a-window-environment-settings-object" style="color:initial">set up a window environment settings object</span>
     <li><span class="dfn-paneled" id="term-for-set-up-a-worker-environment-settings-object" style="color:initial">set up a worker environment settings object</span>
     <li><span class="dfn-paneled" id="term-for-set-up-the-module-script-request" style="color:initial">set up the module script request</span>
     <li><span class="dfn-paneled" id="term-for-settings-object" style="color:initial">settings object</span>
     <li><span class="dfn-paneled" id="term-for-spin-the-event-loop" style="color:initial">spin the event loop</span>
     <li><span class="dfn-paneled" id="term-for-the-script-is-ready" style="color:initial">the script is ready</span>
     <li><span class="dfn-paneled" id="term-for-concept-script-script" style="color:initial">the script's script</span>
     <li><span class="dfn-paneled" id="term-for-concept-script-type" style="color:initial">the script's type</span>
    </ul>
   <li>
    <a data-link-type="biblio">[INFRA]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-ascii-case-insensitive" style="color:initial">ascii case-insensitive</span>
     <li><span class="dfn-paneled" id="term-for-code-unit-less-than" style="color:initial">code unit less than</span>
     <li><span class="dfn-paneled" id="term-for-list-contain" style="color:initial">contain</span>
     <li><span class="dfn-paneled" id="term-for-iteration-continue" style="color:initial">continue</span>
     <li><span class="dfn-paneled" id="term-for-map-exists" style="color:initial">exist</span>
     <li><span class="dfn-paneled" id="term-for-map-iterate" style="color:initial">for each</span>
     <li><span class="dfn-paneled" id="term-for-map-getting-the-keys" style="color:initial">get the keys</span>
     <li><span class="dfn-paneled" id="term-for-struct-item" style="color:initial">item</span>
     <li><span class="dfn-paneled" id="term-for-javascript-string" style="color:initial">javascript string</span>
     <li><span class="dfn-paneled" id="term-for-map-key" style="color:initial">key</span>
     <li><span class="dfn-paneled" id="term-for-ordered-map" style="color:initial">map</span>
     <li><span class="dfn-paneled" id="term-for-ordered-map①" style="color:initial">ordered map</span>
     <li><span class="dfn-paneled" id="term-for-parse-json-into-infra-values" style="color:initial">parse json into infra values</span>
     <li><span class="dfn-paneled" id="term-for-map-sort-in-ascending-order" style="color:initial">sorting</span>
     <li><span class="dfn-paneled" id="term-for-code-unit-prefix" style="color:initial">starts with</span>
     <li><span class="dfn-paneled" id="term-for-string" style="color:initial">string</span>
     <li><span class="dfn-paneled" id="term-for-struct" style="color:initial">struct</span>
    </ul>
   <li>
    <a data-link-type="biblio">[URL]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-concept-url" style="color:initial">url</span>
     <li><span class="dfn-paneled" id="term-for-concept-url-parser" style="color:initial">url parser</span>
     <li><span class="dfn-paneled" id="term-for-concept-url-serializer" style="color:initial">url serializer</span>
    </ul>
   <li>
    <a data-link-type="biblio">[WebIDL]</a> defines the following terms:
    <ul>
     <li><span class="dfn-paneled" id="term-for-exceptiondef-typeerror" style="color:initial">TypeError</span>
    </ul>
  </ul>
  <h2 class="no-num no-ref heading settled" id="references"><span class="content">References</span><a class="self-link" href="#references"></a></h2>
  <h3 class="no-num no-ref heading settled" id="normative"><span class="content">Normative References</span><a class="self-link" href="#normative"></a></h3>
  <dl>
   <dt id="biblio-console">[CONSOLE]
   <dd>Dominic Farolino; Terin Stock; Robert Kowalski. <a href="https://console.spec.whatwg.org/">Console Standard</a>. Living Standard. URL: <a href="https://console.spec.whatwg.org/">https://console.spec.whatwg.org/</a>
   <dt id="biblio-dom">[DOM]
   <dd>Anne van Kesteren. <a href="https://dom.spec.whatwg.org/">DOM Standard</a>. Living Standard. URL: <a href="https://dom.spec.whatwg.org/">https://dom.spec.whatwg.org/</a>
   <dt id="biblio-encoding">[ENCODING]
   <dd>Anne van Kesteren. <a href="https://encoding.spec.whatwg.org/">Encoding Standard</a>. Living Standard. URL: <a href="https://encoding.spec.whatwg.org/">https://encoding.spec.whatwg.org/</a>
   <dt id="biblio-fetch">[FETCH]
   <dd>Anne van Kesteren. <a href="https://fetch.spec.whatwg.org/">Fetch Standard</a>. Living Standard. URL: <a href="https://fetch.spec.whatwg.org/">https://fetch.spec.whatwg.org/</a>
   <dt id="biblio-html">[HTML]
   <dd>Anne van Kesteren; et al. <a href="https://html.spec.whatwg.org/multipage/">HTML Standard</a>. Living Standard. URL: <a href="https://html.spec.whatwg.org/multipage/">https://html.spec.whatwg.org/multipage/</a>
   <dt id="biblio-infra">[INFRA]
   <dd>Anne van Kesteren; Domenic Denicola. <a href="https://infra.spec.whatwg.org/">Infra Standard</a>. Living Standard. URL: <a href="https://infra.spec.whatwg.org/">https://infra.spec.whatwg.org/</a>
   <dt id="biblio-url">[URL]
   <dd>Anne van Kesteren. <a href="https://url.spec.whatwg.org/">URL Standard</a>. Living Standard. URL: <a href="https://url.spec.whatwg.org/">https://url.spec.whatwg.org/</a>
   <dt id="biblio-webidl">[WebIDL]
   <dd>Boris Zbarsky. <a href="https://heycam.github.io/webidl/">Web IDL</a>. URL: <a href="https://heycam.github.io/webidl/">https://heycam.github.io/webidl/</a>
  </dl>
  <h2 class="no-num no-ref heading settled" id="issues-index"><span class="content">Issues Index</span><a class="self-link" href="#issues-index"></a></h2>
  <div style="counter-reset:issue">
   <div class="issue"> Specify a way to set <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope">WorkerGlobalScope</a></code>'s <a data-link-type="dfn" href="#workerglobalscope-import-map">import map</a>. We might want to inherit parent context’s import maps, or provide APIs on <code class="idl"><a data-link-type="idl" href="https://html.spec.whatwg.org/multipage/workers.html#workerglobalscope">WorkerGlobalScope</a></code>, but we are not sure. Currently it is always an <a data-link-type="dfn" href="#empty-import-map">empty import map</a>. See <a href="https://github.com/WICG/import-maps/issues/2">#2</a>.<a href="#issue-53aae9a6"> ↵ </a></div>
   <div class="issue">There are no relevant <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script">script</a>, because <a data-link-type="dfn" href="#import-map-parse-result">import map parse result</a> isn’t a <a data-link-type="dfn" href="https://html.spec.whatwg.org/multipage/webappapis.html#concept-script">script</a>. This needs to wait for <a href="https://github.com/whatwg/html/issues/958">whatwg/html#958</a> before it is fixable.<a href="#issue-3b40327d"> ↵ </a></div>
  </div>
  <aside class="dfn-panel" data-for="specifier-map">
   <b><a href="#specifier-map">#specifier-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-specifier-map">1. Definitions</a> <a href="#ref-for-specifier-map①">(2)</a>
    <li><a href="#ref-for-specifier-map②">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="import-map">
   <b><a href="#import-map">#import-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-import-map">1. Definitions</a>
    <li><a href="#ref-for-import-map①">2.1. New members of environment settings objects</a> <a href="#ref-for-import-map②">(2)</a> <a href="#ref-for-import-map③">(3)</a>
    <li><a href="#ref-for-import-map④">2.2. Script type</a>
    <li><a href="#ref-for-import-map⑤">2.3. Prepare a script</a>
    <li><a href="#ref-for-import-map⑥">3. Parsing import maps</a> <a href="#ref-for-import-map⑦">(2)</a> <a href="#ref-for-import-map⑧">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="import-map-imports">
   <b><a href="#import-map-imports">#import-map-imports</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-import-map-imports">1. Definitions</a>
    <li><a href="#ref-for-import-map-imports①">3. Parsing import maps</a> <a href="#ref-for-import-map-imports②">(2)</a>
    <li><a href="#ref-for-import-map-imports③">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="import-map-scopes">
   <b><a href="#import-map-scopes">#import-map-scopes</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-import-map-scopes">1. Definitions</a>
    <li><a href="#ref-for-import-map-scopes①">3. Parsing import maps</a> <a href="#ref-for-import-map-scopes②">(2)</a>
    <li><a href="#ref-for-import-map-scopes③">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="empty-import-map">
   <b><a href="#empty-import-map">#empty-import-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-empty-import-map">2.1. New members of environment settings objects</a> <a href="#ref-for-empty-import-map①">(2)</a> <a href="#ref-for-empty-import-map②">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="environment-settings-object-import-map">
   <b><a href="#environment-settings-object-import-map">#environment-settings-object-import-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-environment-settings-object-import-map">2.1. New members of environment settings objects</a> <a href="#ref-for-environment-settings-object-import-map①">(2)</a>
    <li><a href="#ref-for-environment-settings-object-import-map②">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="document-import-map">
   <b><a href="#document-import-map">#document-import-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-document-import-map">2.1. New members of environment settings objects</a>
    <li><a href="#ref-for-document-import-map①">2.5. Registering an import map</a> <a href="#ref-for-document-import-map②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="workerglobalscope-import-map">
   <b><a href="#workerglobalscope-import-map">#workerglobalscope-import-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-workerglobalscope-import-map">2.1. New members of environment settings objects</a> <a href="#ref-for-workerglobalscope-import-map①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="document-pending-import-map-script">
   <b><a href="#document-pending-import-map-script">#document-pending-import-map-script</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-document-pending-import-map-script">2.3. Prepare a script</a> <a href="#ref-for-document-pending-import-map-script①">(2)</a> <a href="#ref-for-document-pending-import-map-script②">(3)</a> <a href="#ref-for-document-pending-import-map-script③">(4)</a> <a href="#ref-for-document-pending-import-map-script④">(5)</a>
    <li><a href="#ref-for-document-pending-import-map-script⑤">2.4. Wait for import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="document-acquiring-import-maps">
   <b><a href="#document-acquiring-import-maps">#document-acquiring-import-maps</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-document-acquiring-import-maps">2.3. Prepare a script</a>
    <li><a href="#ref-for-document-acquiring-import-maps①">2.4. Wait for import maps</a> <a href="#ref-for-document-acquiring-import-maps②">(2)</a> <a href="#ref-for-document-acquiring-import-maps③">(3)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="import-map-parse-result">
   <b><a href="#import-map-parse-result">#import-map-parse-result</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-import-map-parse-result">2.2. Script type</a> <a href="#ref-for-import-map-parse-result①">(2)</a>
    <li><a href="#ref-for-import-map-parse-result②">2.5. Registering an import map</a> <a href="#ref-for-import-map-parse-result③">(2)</a>
    <li><a href="#ref-for-import-map-parse-result④">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="import-map-parse-result-settings-object">
   <b><a href="#import-map-parse-result-settings-object">#import-map-parse-result-settings-object</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-import-map-parse-result-settings-object">2.5. Registering an import map</a>
    <li><a href="#ref-for-import-map-parse-result-settings-object①">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="import-map-parse-result-import-map">
   <b><a href="#import-map-parse-result-import-map">#import-map-parse-result-import-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-import-map-parse-result-import-map">2.5. Registering an import map</a>
    <li><a href="#ref-for-import-map-parse-result-import-map①">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="import-map-parse-result-error-to-rethrow">
   <b><a href="#import-map-parse-result-error-to-rethrow">#import-map-parse-result-error-to-rethrow</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-import-map-parse-result-error-to-rethrow">2.5. Registering an import map</a> <a href="#ref-for-import-map-parse-result-error-to-rethrow①">(2)</a>
    <li><a href="#ref-for-import-map-parse-result-error-to-rethrow②">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="the-scripts-result">
   <b><a href="#the-scripts-result">#the-scripts-result</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-the-scripts-result">2.3. Prepare a script</a>
    <li><a href="#ref-for-the-scripts-result①">2.5. Registering an import map</a> <a href="#ref-for-the-scripts-result②">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="fetch-an-import-map">
   <b><a href="#fetch-an-import-map">#fetch-an-import-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-fetch-an-import-map">2.3. Prepare a script</a> <a href="#ref-for-fetch-an-import-map①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="wait-for-import-maps">
   <b><a href="#wait-for-import-maps">#wait-for-import-maps</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-wait-for-import-maps">2.3. Prepare a script</a>
    <li><a href="#ref-for-wait-for-import-maps①">2.4. Wait for import maps</a> <a href="#ref-for-wait-for-import-maps②">(2)</a> <a href="#ref-for-wait-for-import-maps③">(3)</a>
    <li><a href="#ref-for-wait-for-import-maps④">2.5. Registering an import map</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="register-an-import-map">
   <b><a href="#register-an-import-map">#register-an-import-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-register-an-import-map">2.2. Script type</a>
    <li><a href="#ref-for-register-an-import-map①">2.3. Prepare a script</a>
    <li><a href="#ref-for-register-an-import-map②">2.5. Registering an import map</a> <a href="#ref-for-register-an-import-map③">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="parse-an-import-map-string">
   <b><a href="#parse-an-import-map-string">#parse-an-import-map-string</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-parse-an-import-map-string">3. Parsing import maps</a>
    <li><a href="#ref-for-parse-an-import-map-string①">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="create-an-import-map-parse-result">
   <b><a href="#create-an-import-map-parse-result">#create-an-import-map-parse-result</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-create-an-import-map-parse-result">2.3. Prepare a script</a> <a href="#ref-for-create-an-import-map-parse-result①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="sort-and-normalize-a-specifier-map">
   <b><a href="#sort-and-normalize-a-specifier-map">#sort-and-normalize-a-specifier-map</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-sort-and-normalize-a-specifier-map">3. Parsing import maps</a> <a href="#ref-for-sort-and-normalize-a-specifier-map①">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="sort-and-normalize-scopes">
   <b><a href="#sort-and-normalize-scopes">#sort-and-normalize-scopes</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-sort-and-normalize-scopes">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="normalize-a-specifier-key">
   <b><a href="#normalize-a-specifier-key">#normalize-a-specifier-key</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-normalize-a-specifier-key">3. Parsing import maps</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="parse-a-url-like-import-specifier">
   <b><a href="#parse-a-url-like-import-specifier">#parse-a-url-like-import-specifier</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-parse-a-url-like-import-specifier">3. Parsing import maps</a> <a href="#ref-for-parse-a-url-like-import-specifier①">(2)</a>
    <li><a href="#ref-for-parse-a-url-like-import-specifier②">4.1. New "resolve a module specifier"</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="resolve-a-module-specifier">
   <b><a href="#resolve-a-module-specifier">#resolve-a-module-specifier</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-resolve-a-module-specifier">2.4. Wait for import maps</a> <a href="#ref-for-resolve-a-module-specifier①">(2)</a>
    <li><a href="#ref-for-resolve-a-module-specifier④">4.2. Updates to other algorithms</a> <a href="#ref-for-resolve-a-module-specifier⑤">(2)</a>
   </ul>
  </aside>
  <aside class="dfn-panel" data-for="resolve-an-imports-match">
   <b><a href="#resolve-an-imports-match">#resolve-an-imports-match</a></b><b>Referenced in:</b>
   <ul>
    <li><a href="#ref-for-resolve-an-imports-match">4.1. New "resolve a module specifier"</a> <a href="#ref-for-resolve-an-imports-match①">(2)</a>
   </ul>
  </aside>
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